System and method for control based on face or hand gesture detection

ABSTRACT

System and method for control using face detection or hand gesture detection algorithms in a captured image. Based on the existence of a detected human face or a hand gesture in an image captured by a digital camera, a control signal is generated and provided to a device. The control may provide power or disconnect power supply to the device (or part of the device circuits). The location of the detected face in the image may be used to rotate a display screen to achieve a better line of sight with a viewing person. The difference between the location of the detected face and an optimum is the error to be corrected by rotating the display to the required angular position. A hand gesture detection can be used as a replacement to a remote control for the controlled unit, such as a television set.

FIELD OF THE INVENTION

The present invention relates generally to devices (such as displays)controlled by face detection.

BACKGROUND OF THE INVENTION

In most display devices, the best visual quality is obtained when theobserver is exactly in front of the surface wherein the image isdisplayed, thus having the widest angular field of view and maximumperceived area. Further, in many types of displays (such as LCD andplasma based panels), the luminance and the contrast are decreased whenthe viewing direction is deviated from the direction which is verticalto the display surface, both in the inclination and azimuth directions.In some cases, a viewing cone is defined, limiting the availabledirections from which the image can be viewed. ISO 13406-21 titled“Ergonomic requirements for work with visual displays based on flatpanels—Part 2: Ergonomic requirements for flat panel displays” providesa classification of Viewing Direction Range Classes and ReflectionClasses.

An autorotative digital photo frame adapted to allow the frame to beadjusted to the same direction as the photo is disclosed in U.S. PatentApplication Publication 2008/0236014 to Chao et al. entitled:“Autorotative Digital Photo Frame”, which is incorporated in itsentirety for all purposes as if fully set forth herein.

In consideration of the foregoing, it would be an advancement in the artto provide a method and system that is simple, cost-effective, faithful,reliable, has a minimum part count, minimum hardware, or uses existingand available components allowing convenient or better control orvisualization of a device, and in particular a display, such as atelevision set. Furthermore, it would be highly advantageous to have amethod and system providing a simpler, better and easier control of adevice without using a remote control.

SUMMARY OF THE INVENTION

In one aspect of the invention a method and apparatus for using facedetection functionality for obtaining a good visibility with a screen ofa display. A digital camera is attached to a display having a centralimage captured substantially congruent with the display planeline-of-sight. A face detection algorithm is performed by an imageprocessor, using the image captured by the digital camera to obtain theexistence and localization of faces in the captured image. Thehorizontal deviation of a detected face from the image center line iscalculated. The camera and the image processor serve as a sensorproviding the horizontal deviation value and direction. A control loop(open or closed) uses the horizontal deviation as an error signal, and acontroller command a horizontal motor mechanically affixed to thedisplay to rotate the display in the required direction (and the angularshift required) to correct for the deviation (set point zero). A closedloop may be employed for minimizing the deviation continuously.

In one aspect of the invention, the vertical deviation of a detectedface from the image center line is calculated. The camera and the imageprocessor serve as a sensor providing the vertical deviation value anddirection. A control loop (open or closed) uses the vertical deviationas an error signal, and a controller command a vertical motormechanically affixed to the display to rotate the display in therequired direction (and the angular shift required) for inclinator tocorrect for the deviation (set point zero). A closed loop may beemployed for minimizing the deviation continuously.

In one aspect of the invention, both the vertical and horizontaldeviations of a detected face from the image center line are calculated.The camera and the image processor serve as a sensor providing thevertical and horizontal deviations values and directions. Independentvertical and horizontal control loops (each may be open or closed) areused, each uses the respective deviation as an error signal, and acontroller command a respective vertical or horizontal motormechanically affixed to the display to rotate the display in thedirection required (and the angular shift required) to correct for thedeviation (set point zero). A closed loop may be employed for minimizingthe deviation continuously.

In one aspect of the invention, a negative feedback control loop isused. Further, linear control loop may be used. Further, the loop mayuse proportional-only control loop, or PID (Proportional, Integral,Derivative) control loop.

According to one aspect on the invention, a method for improving theangular field of view of a person watching a display having a screen isdescribed, the method comprising the steps of capturing an image acrossthe display screen, converting the image into a digital data form,detecting an human face in the captured image using image processingalgorithm, calculating the deviation between the detected face locationin the captured image and the image center, and rotating the display inthe direction required to reduce the calculated deviation. The steps maybe executed once or executed, repeatedly until the calculated deviationis smaller than a pre defined value, thus implementing a linear feedbackcontrol loop, wherein the error is the calculated deviation, the setpoint is zero and the angular rotation of the display is the actuatorcontrolled by the loop. The loop may be a linear proportional controlloop only, wherein the amount of angular rotation is proportional to thecalculated deviation, or a PID (Proportional, Integral and Derivative)control loop wherein the amount of angular rotation is calculated basedon proportional, integral and derivative computations of the calculateddeviation.

The method may be handling only the horizontal positioning, wherein thehorizontal deviation is calculated in the captured image, and whereinthe rotation of the display is in the horizontal plane, or handling onlythe vertical positioning, wherein the vertical deviation is calculatedin the captured image, and wherein the rotation of the display is in thevertical plane, or handling both vertical and horizontal functions.

If no human face is detected, no rotation is executed. If two or morehuman faces are detected in the captured image, then the average pointof the detected faces is calculated, and the deviation is calculatedbetween the average point and the image center.

According to one aspect on the invention, an apparatus for improving theangular field of view of a person watching a display having a screen isdescribed. The apparatus comprising a digital camera for capturing animage in a digital data form, the camera is mechanically attached to thedisplay and oriented to capture the view substantially across thedisplay screen, an image processor coupled to receive the image in adigital data form from the digital camera, for applying face detectionalgorithm to detect and locate a human face location in the capturedimage, and a motor mechanically attached to the display for angularlyrotating the display, wherein the apparatus is operative to rotate themotor in response to the location of the detected face in the capturedimage. The apparatus may further comprise a firmware or software and acontroller executing the firmware or software coupled between thedigital camera and the motor for commanding the motor (which may be astepper motor) rotation in response to the location of the detected facein the captured image.

The deviation may be calculated between the detected face location andthe image center, and wherein the motor angular rotation is based on thecalculated deviation. Further, no motor rotation may be required in thecase wherein the calculated deviation is smaller than a pre definedvalue. The apparatus may continuously rotate the motor in response tothe location of the detected face in the captured image, defining adefining a linear feedback control loop, wherein the error is thecalculated deviation, the set point is zero and the angular rotation ofthe display is the actuator controlled by the loop. The control loop maybe linear proportional control loop, wherein the amount of angularrotation is proportional to the calculated deviation, or a PID(Proportional, Integral and Derivative) control loop wherein the amountof angular rotation is calculated based on proportional, integral andderivative computations of the calculated deviation.

The apparatus may handle only the horizontal plane wherein thehorizontal deviation is calculated in the captured image and wherein themotor is attached to effect display rotation in the horizontal plane.Alternatively, the apparatus may handle only the vertical plane whereinthe vertical deviation is calculated in the captured image and whereinthe motor is attached to effect display rotation in the vertical plane.Alternatively both planes are handles simultaneously.

In the case wherein two or more human faces are detected in the capturedimage, then the average point of the detected faces is calculated by theimage processor, the deviation is calculated between the average pointand the image center.

According to one aspect on the invention, a method for controlling adevice based on face detection is described, comprising the steps ofcapturing an image, converting the image into a digital data form, usingimage processing algorithm for detecting an human face in the capturedimage, and providing a control signal in response to the detection of anhuman face in the captured image. These steps can be executed once orexecuted repeatedly, and may further include waiting a pre-set periodbefore repeating the steps.

The method may control supplying power to the device is response to thedetection of a human face in the captured image, or controldisconnecting power to the device is response to not detecting a humanface in the captured image.

The device may be a display or a television set, and the image may becaptured substantially across the display screen. Further, the displaymay be blanked in response to not detecting a human face in the capturedimage.

Further, the control signal may be generated in response to detecting ahuman face in the captured image for a pre-defined period or lacking ofsuch detection. Further, a first control signal may generated inresponse to not detecting a human face in the captured image for a firstpre-defined period, and a second control signal may be generated inresponse to detecting a human face in the captured image for a secondpre-defined period.

The control signal may involve supplying power to the device, whereinthe control signal involves disconnecting power to the device or part ofthe device circuits.

According to one aspect on the invention, an apparatus for facedetection based control of a device is described, comprising a digitalcamera for capturing an image in a digital data form, an image processorcoupled to receive the image in a digital data form from the digitalcamera, for applying face detection algorithm to detect a human faceoccurrence in the captured image, and a controller coupled to the imageprocessor for generating a control signal is response to the detectionof an human face in the captured image. The apparatus may furthercomprise a firmware or software and the controller is executing thefirmware or software, and the camera may be mechanically attached to thecontrolled device. Further, the image processor and the controller maybe housed within a single enclosure.

The apparatus may further comprise a switch actuated by said controlsignal and the switch may be connected between a power source and thedevice, for powering the device is response to the control signal. Thus,the apparatus may actuate the switch for supplying power to the devicein response to the detection (or lack of detection or both) of a humanface in the captured image. The switch may be housed within the deviceenclosure. Further, the apparatus may use one or two timers forsignaling a pre-set first period coupled or within the controller, suchthat the control signal is generated in response to detecting (or lackof detecting or both) a human face in the captured image for apre-defined period. Further, the control signal may involve supplyingpower or disconnecting power to or from the device. The device may be adisplay, and the camera may be positioned such that the image capturedis substantially across the display screen, and the display may beblanked in response to not detecting a human face in the captured image.

According to one aspect on the invention, a method for controlling adevice based on hand gesture detection is described, the methodcomprising the steps of capturing an image, converting the image into adigital data form, using image processing algorithm for detecting anhand gesture in said captured image, and providing a control signal inresponse to the detection of the hand gesture in said captured image.These steps can be executed one time or executed repeatedly, with orwithout waiting a pre-set period before repeating the steps. The methodmay further comprise the step of supplying or disconnecting power to thedevice is response to the detection of a hand gesture in said capturedimage. The device may be a display or a television set, and the imagecaptured may be substantially across the display screen. Further, thedisplay may be blanked in response to not detecting a hand gesture inthe captured image.

One or more control signals may be generated, in response to detectingor not detecting a hand gesture in said captured image for a pre-definedperiod. The control signal may involve supplying power or disconnectingpower (or both) to the device.

The hand gesture may involve extending a single finger, multiple or allfingers. One or multiple pre-defined hand gesture can be detected and adedicated control may be associated with each detected hand gesture.

The method may be combined with the step of using image processingalgorithm for detecting a human face in said captured image, and acontrol signal may be provided only in response to the detection of boththe hand gesture and detecting a human face in said captured image.Further, only a specific area in the image may be analyzed for handgesture detection, based on the location of the detected face.

According to one aspect on the invention, an apparatus for hand gesturedetection based control of a device is described, comprising a digitalcamera for capturing an image in a digital data form, an image processorcoupled to receive the image in a digital data form from the digitalcamera, for applying hand gesture detection algorithm to detect a handgesture occurrence in the captured image, and a controller coupled tothe image processor for generating a control signal is response to thedetection of a hand gesture in the captured image. The apparatus mayfurther comprise a firmware or software and the controller is executingthe firmware or software, and the camera may be mechanically attached tothe controlled device. Further, the image processor and the controllermay be housed within a single enclosure.

The apparatus may further comprise a switch actuated by said controlsignal and the switch may be connected between a power source and thedevice, for powering the device is response to the control signal. Thus,the apparatus may actuate the switch for supplying power to the devicein response to the detection (or lack of detection or both) of a handgesture in the captured image. The switch may be housed within thedevice enclosure. Further, the apparatus may use one or two timers forsignaling a pre-set first period coupled or within the controller, suchthat the control signal is generated in response to detecting (or lackof detecting or both) a hand gesture in the captured image for apre-defined period. Further, the control signal may involve supplyingpower or disconnecting power to or from the device. The device may be adisplay, and the camera may be positioned such that the image capturedis substantially across the display screen, and the display may beblanked in response to not detecting a hand gesture in the capturedimage.

One or more control signals may be generated, in response to detectingor not detecting a hand gesture in said captured image for a pre-definedperiod. The control signal may involve supplying power or disconnectingpower (or both) to the device.

The hand gesture may involve extending a single finger, multiple or allfingers. One or multiple pre-defined hand gesture can be detected and adedicated control may be associated with each detected hand gesture.

The apparatus may be combined with image processing algorithm fordetecting a human face in said captured image, and a control signal maybe provided only in response to the detection of both the hand gestureand detecting a human face in said captured image. Further, only aspecific area in the image may be analyzed for hand gesture detection,based on the location of the detected face.

The camera may be mechanically attached to the display or be a separatedevice housed within a separate enclosure. The digital data representingthe captured image is transmitted from the camera over a communicationmedium to an image processor in a control box. The control box receivesthe digital data from the communication medium and processes it. In thisscenario, the camera includes a transmitter (or a transceiver) fortransmitting the image digital data to the communication medium, and thecontrol box includes a receiver (or a transceiver) for receiving thedigital data from the communication medium. In one aspect according tothe invention, the video signal is carried in an analog form over thecommunication medium, respectively using an analog transmitter and ananalog receiver.

The communication between the camera assembly and the image processor,as well the communication between the control box and the controlledunit, can be non-conductive over-the-air wireless, using radio, audio orlight based communication, and use various WLAN, WPAN and othertechnologies. The wireless communication may use a spread-spectrumsignal such as multi-carrier (e.g. OFDM, DMT and CDMA), or a singlecarrier (narrow-band) signal. Each of the wireless signals or thewireless communication links above may be WPAN, WLAN, WMAN, WAN, BWA,LMDS, MMDS, WiMAX, HIPERMAN, IEEE802.16, Bluetooth, IEEE802.15,IEEE802.11 (such as a, b and g), UWB, ZigBee and cellular such as GSM,GPRS, 2.5G, 3G, UMTS, DCS, PCS and CDMA. Similarly, each of thefrequency bands above may be part of the ISM frequency bands.

Alternatively, the power and communication signals may be carried overthe same wires using Frequency Division Multiplexing (FDM), wherein thepower signal is carried over a power frequency, and wherein thecommunication signal is carried over a communication frequency banddistinct and above the power frequency. In this case, the device mayfurther include a low pass filter coupled between the connector and thetransmitter for substantially passing only the power frequency, forpowering the transmitter from the power signal. Such device may alsofurther include a high pass filter coupled between the connector and thetransmitter for substantially passing only the communication frequencyband, for passing the communication signal between the connector and thetransmitter. In the case where power is AC power, the connector may bean AC power plug for connecting to AC power wiring, and the transmittermay be part of a powerlines modem, such as HomePlug or UPB.

Further, such communication can use a conductive medium such as cablesor wires, or any other metallic medium. Standard PAN or LAN cabling andprotocols may be used, such as Ethernet 10/100/1000BaseT. In oneembodiment, powerline communication is used wherein the AC power wiringis used as the communication medium.

In another aspect of the present invention, a lossy or non-lossycompression of the image information is used for reducing the memorysize and reducing the data rate required for the transmission over thecommunication medium.

According to one aspect on the invention, the face detection or the handgesture detection (or both) are used to control devices other than adisplay.

In one aspect of the invention, the communication medium between thecamera assembly and the image processor, or the communication betweenthe control box and the controlled unit or both communication links, isa wired medium, and a transmitter is used as a wired transmitter adaptedto transmit digital data to the wired medium. The communication over thewired medium may be according to a wired PAN (Personal Area Network) ora LAN (Local area Network) standard, and may further be based on serialor parallel transmission. For example, the wired medium may be a LANcable substantially according to EIT/TIA-568 or EIA/TIA-570 containing aUTP (unshielded Twisted Pair) or STP (Shielded Twisted Pair). In suchcase the connector is an RJ-45 type, and the communication over thecable may substantially conform to IEEE802.3 Ethernet 10BaseT or100BaseTX or 1000BaseT, and the transmitter may be a LAN transceiver. Inan alternative aspect, the wired transmitter and the connectorsubstantially conform to one out of IEEE1394, USB (Universal SerialBus), EIA/TIA-232 and IEEE1284.

In one aspect of the invention, the communication between the cameraassembly and the image processor, or the communication between thecontrol box and the controlled unit or both communication links, uses awired medium such as a cable. Further, the cable concurrently carries apower signal, and the device is at least in part powered from the powersignal. The power signal may be a DC (Direct Current) power signal, oran AC (Alternating Current) power signal. The cable may contain multipleinsulated wires, and the power signal may be carried over dedicatedwires distinct from the wires carrying the communication signal. In thecase wherein the cable contains multiple insulated wires, and the wiresare used to simultaneously carry both power and communication signals,the power and communication signals are carried over the same wires. Insuch a case the power may be a DC power carrying over a phantom channelover the wires. For example, the cable may be a LAN cable substantiallyaccording to EIT/TIA-568 or EIA/TIA-570 and containing UTP or STPtwisted-pairs, the connector may be RJ-45 type, the communication overthe cable may substantially conform to IEEE802.3 Ethernet 10BaseT,100BaseTX, or 1000BaseT, the transmitter may be a LAN transceiver, andthe power may be carried over the cable substantially according toIEEE802.3af or IEEE802.3 at standards.

In another aspect of the present invention, a single cable is used toconnect between the camera assembly and the image processor, or betweenthe control box and the controlled unit or both. The cablesimultaneously carries both the communication signal for displaying thecaptured image on the display, and a power signal. The power signal canbe fed from the control box to power the camera, or alternately fed fromthe camera to power the control box. Carrying both the power and datasignals over the same cable can make use of distinct separated wiresets, each set dedicated to one type of a signal. Alternatively, thesame wires can carry both signals each over a different frequency band(FDM) or using phantom technique.

The above summary is not an exhaustive list of all aspects of thepresent invention. Indeed, the inventor contemplates that his inventionincludes all systems and methods that can be practiced from all suitablecombinations and derivatives of the various aspects summarized above, aswell as those disclosed in the detailed description below andparticularly pointed out in the claims filed with the application. Suchcombinations have particular advantages not specifically recited in theabove summary.

It is understood that other embodiments of the present invention willbecome readily apparent to those skilled in the art from the followingdetailed description, wherein are shown and described only embodimentsof the invention by way of illustration. As will be realized, theinvention is capable of other and different embodiments and its severaldetails are capable of modification in various other respects, allwithout departing from the scope of the present invention as defined bythe claims. Accordingly, the drawings and detailed description are to beregarded as illustrative in nature and not as restrictive.

The above and other features and advantages of the present inventionwill become more fully apparent from the following description, drawingsand appended claims, or may be learned by the practice of the inventionas set forth hereinafter. It is intended that all such additionalapparatus and advantages be included within this description, be withinthe scope of the present invention, and be protected by the accompanyingclaims.

BRIEF DESCRIPTION OF THE DRAWINGS

In order that the manner in which the above recited and other advantagesand features of the invention are obtained, a more particulardescription of the invention briefly described above will be rendered byreference to specific embodiments thereof, which are illustrated in theappended figures and drawings. The invention is herein described, by wayof non-limiting example only, with reference to the accompanying figuresand drawings, wherein like designations denote like elements.Understanding that these drawings only provide information concerningtypical embodiments of the invention and are not therefore to beconsidered limiting in scope:

FIG. 1 illustrates schematically a simplified general functional blockdiagram of a system according to the invention;

FIG. 2 illustrates schematically a perspective front view of a systemaccording to the invention;

FIG. 3 illustrates schematically a perspective rear view of a systemaccording to the invention;

FIG. 4 illustrates schematically a rear view of a system according tothe invention;

FIG. 5 illustrates schematically a top view of a system according to theinvention;

FIG. 6 illustrates schematically a side view of a system according tothe invention;

FIG. 7 illustrates schematically a simplified general functional blockdiagram of a prior-art electronic camera;

FIG. 8 illustrates schematically a rear view of a system according tothe invention;

FIG. 9 illustrates schematically a top view of a system according to theinvention;

FIG. 10 illustrates schematically a flow chart of the system operationaccording to the invention;

FIG. 11 illustrates schematically a perspective view of a room with asystem according to the invention;

FIG. 12 illustrates schematically a perspective view of a room with asystem according to the invention;

FIG. 13 illustrates schematically a side view of a room with a systemaccording to the invention;

FIG. 14 illustrates schematically a top view of a room with a systemaccording to the invention;

FIG. 15 illustrates schematically an image captured and analyzed in asystem according to the invention;

FIG. 16 illustrates schematically a top view of a room with a systemaccording to the invention;

FIG. 17 illustrates schematically an image captured and analyzed in asystem according to the invention;

FIG. 18 illustrates schematically a top view of a room with a systemaccording to the invention;

FIG. 19 illustrates schematically an image captured and analyzed in asystem according to the invention;

FIG. 20 illustrates schematically a top view of a room with a systemaccording to the invention;

FIG. 21 illustrates schematically a perspective view of a room with asystem according to the invention;

FIG. 23 illustrates schematically a side view of a room with a systemaccording to the invention;

FIG. 24 illustrates schematically an image captured and analyzed in asystem according to the invention;

FIG. 25 illustrates schematically a top view of a room with a systemaccording to the invention;

FIG. 26 illustrates schematically an image captured and analyzed in asystem according to the invention;

FIG. 27 illustrates schematically an image captured and analyzed in asystem according to the invention;

FIG. 28 illustrates schematically an image captured and analyzed in asystem according to the invention;

FIG. 29 illustrates schematically a top view of a room with a systemaccording to the invention;

FIG. 30 illustrates schematically a simplified general functional blockdiagram of a system according to the invention;

FIG. 31 illustrates schematically a perspective front view of a systemaccording to the invention;

FIG. 32 illustrates schematically a perspective rear view of a systemaccording to the invention;

FIG. 33 illustrates schematically a side view of a system according tothe invention;

FIG. 34 illustrates schematically a perspective side view of a systemaccording to the invention;

FIG. 35 illustrates schematically an image captured and analyzed in asystem according to the invention;

FIG. 36 illustrates schematically a simplified general functional blockdiagram of a system according to the invention;

FIG. 37 illustrates schematically a perspective front view of a systemaccording to the invention;

FIG. 38 illustrates schematically a perspective rear view of a systemaccording to the invention;

FIG. 39 illustrates schematically a perspective front view of a systemaccording to the invention;

FIG. 40 illustrates schematically a flow chart of the system operationaccording to the invention;

FIG. 41 illustrates schematically a simplified general functional blockdiagram of a system according to the invention;

FIG. 42 illustrates schematically a simplified general functional blockdiagram of a system according to the invention;

FIG. 43 illustrates schematically a perspective front view of a roomaccording to the invention;

FIG. 44 illustrates schematically a side view of a room according to theinvention;

FIG. 45 illustrates schematically a top view of a room according to theinvention;

FIG. 46 illustrates schematically an image captured and analyzed in asystem according to the invention;

FIG. 47 illustrates schematically an image captured and analyzed in asystem according to the invention;

FIG. 48 illustrates schematically an image captured and analyzed in asystem according to the invention;

FIG. 49 illustrates schematically an image captured and analyzed in asystem according to the invention;

FIG. 50 illustrates schematically an image captured and analyzed in asystem according to the invention;

FIG. 51 illustrates schematically a flow chart of the system operationaccording to the invention;

FIG. 52 illustrates schematically a flow chart of the system operationaccording to the invention;

FIG. 53 illustrates schematically an image captured and analyzed in asystem according to the invention;

FIG. 54 illustrates schematically an image captured and analyzed in asystem according to the invention.

FIG. 55 illustrates schematically a simplified general functional blockdiagram of a system according to the invention;

FIG. 56 illustrates schematically a simplified general functional blockdiagram of a system according to the invention;

FIG. 57 illustrates schematically a simplified general functional blockdiagram of a system according to the invention;

FIG. 58 illustrates schematically a simplified general functional blockdiagram of a system according to the invention;

FIG. 59 illustrates schematically a simplified general functional blockdiagram of a system according to the invention; and

FIG. 60 illustrates schematically a simplified general functional blockdiagram of a system according to the invention.

DETAILED DESCRIPTION OF EMBODIMENTS

The principles and operation of a network according to the presentinvention may be understood with reference to the figures and theaccompanying description wherein similar components appearing indifferent figures are denoted by identical reference numerals. Thedrawings and descriptions are conceptual only. In actual practice, asingle component can implement one or more functions; alternatively,each function can be implemented by a plurality of components andcircuits. In the figures and descriptions, identical reference numeralsindicate those components that are common to different embodiments orconfigurations. Identical numerical references (even in the case ofusing different suffix, such as 5, 5 a, 5 b and 5 c) refer to functionsor actual devices that are either identical, substantially similar orhaving similar functionality. It will be readily understood that thecomponents of the present invention, as generally described andillustrated in the figures herein, could be arranged and designed in awide variety of different configurations. Thus, the following moredetailed description of the embodiments of the apparatus, system, andmethod of the present invention, as represented in the figures herein,is not intended to limit the scope of the invention, as claimed, but ismerely representative of embodiments of the invention.

FIG. 1 is a schematic block diagram of a system 10 according to oneembodiment of the invention. A pictorial front perspective view 20 ofthe system is shown in FIG. 2, a rear perspective view 30 is shown inFIG. 3, a rear view 40 is shown in FIG. 4, an up view 50 is shown inFIG. 5 and side view 60 is shown in FIG. 6.

The invention is exampled with regard to a flat panel display 18, forexample a LCD television set. However, any other electronic display orany other output device used for presentation of visual information maybe equally used. Common applications for electronic visual displays usedto be television sets or computer monitors. The display 18 may be adigital or analog video display, and may use technologies such as LCD(Liquid Crystal Display), TFT (Thin-Film Transistor), FED (FieldEmission Display), CRT (Cathode Ray Tube) or any other electronic screentechnology that visually shows information such as graphics or text. Inmany cases, an adaptor (not shown) is required in order to connect ananalog display to the digital data. For example, the adaptor may convertto composite video (PAL, NTSC) or S-Video or HDTV signal. Various usercontrols can be available to allow the user to control and effect thedisplay unit 18 operations, such as an on/off switch, a reset button andothers. Other exemplary controls involve display associated settingssuch as contrast, brightness and zoom.

Analog displays are commonly using interfaces such as composite videosuch as NTSC, PAL or SECAM formats. Similarly, analog RGB, VGA (VideoGraphics Array), SVGA (Super Video Graphics Array), SCART, S-video andother standard analog interfaces can be used. Further, personal computermonitors, plasma or flat panel displays, CRT, DLP display or a videoprojector may be equally used. Standard digital interfaces such as aIEEE1394 interface, also known as FireWire™, may be used. Other digitalinterfaces that can be used are USB, SDI (Serial Digital Interface),FireWire, HDMI (High-Definition Multimedia Interface), DVI (DigitalVisual Interface), UDI (Unified Display Interface), DisplayPort, DigitalComponent Video and DVB (Digital Video Broadcast).

Display 18 is mechanically mounted using a pedestal 28 attached to therear part of the display 18. The pedestal 18 is attached to axis 17 ofthe electric motor 15. The motor 15 converts electrical energy intorotational motion of its axis. The torque applied to the motor axis 17rotates the display 18 horizontally via the pedestal 28 around itsvertical center. This allows rotating and positioning the display 18 asrequired by controlling the electric motor 15. The motor 15 is mountedon and fixed to base 29 which is placed on drawer's chest 27. The base29 provides support to the mechanical assembly including the display 18,pedestal 28 and the motor 15. The electric motor 15 is controlled andpowered by control box 11, and connected thereto via cable 23 (shownconnected via the base 29).

FIG. 8 shows a perspective rear view 80 and FIG. 9 shows an up view 90of the system after angular rotating of the display 18 by the motor 15from the original position shows as dashed lines 91 in FIG. 9.

The electric motor 15 can be of Alternating Current (AC) or DirectCurrent (DC) powered type. In the case of AC powered motor, the motormay be either synchronous or induction type. In the case of a DC poweredmotor, the motor may either be brushless or stepper type. The motor iscontrolled by motor controller 14 in the control box 11. The motorcontroller 14 might include a manual or automatic means for starting andstopping the motor, selecting forward or reverse rotation, selecting andregulating the speed, regulating or limiting the torque, and protectingagainst overloads and faults. An electric motor controller is commonlysuited to the type of motor it is to drive such as permanent magnet,servo, series, separately excited, and alternating current.

A system according to one embodiment of the invention comprises anelectronic camera 16. The camera 16 is attached to the display 18.Preferably, the camera 16 is attached to the display 18 such that thecamera 16 center line-of-sight is substantially parallel to the display18 center line of sight, so that the center of the image captured by thecamera 16 is congruent with a perpendicular line erecting from thecenter panel of the display 16. Camera 16 may be a still camera whichconverts captured image into electric signal upon a specific control, orcan be a video camera, wherein the conversion between captured images toelectronic signal is continuous (e.g. 24 frames per second).ispreferable a digital camera. Camera 16 is preferably a digital camera,wherein the video or still images are converted using electronic imagesensor. An electronic signal representing the captured image istransmitted from the camera 16 to the image processor 12 in the controlbox 11 via cable 26. The signal may be digital or analog signal.

Block diagram of such digital camera 16 is shown in FIG. 7, showing lens71 (or few lenses) for focusing the received light onto a smallsemiconductor sensor 72. The sensor 72 commonly includes a panel with amatrix of tiny light-sensitive diodes (photocells), converting the imagelight to electric charges and then to electric signals, thus creating avideo picture or a still image by recording the light intensity.Charge-Coupled Devices (CCD) and CMOS (ComplementaryMetal-Oxide-Semiconductor) are commonly used as the light-sensitivediodes. Linear or area arrays of light-sensitive elements may be used,and the light sensitive sensors may support monochrome (black & white),color or both. For example, the CCD sensor KAI-2093 Image Sensor 1920(H) X 1080 (V) Interline CCD Image Sensor or KAF-50100 Image Sensor 8176(H) X 6132 (V) Full-Frame CCD Image Sensor can be used, available fromImage Sensor Solutions, Eastman Kodak Company, Rochester, N.Y..

An image processor block 73 receives the analog signal from the imagesensor. The Analog Front End (AFE) in the block 73 filters, amplifiesand digitizes the signal, using an analog-to-digital (A/D) converter.The AFE further provides correlated double sampling (CDS), and providesa gain control to accommodate varying illumination conditions. In thecase of CCD sensor 72, a CCD AFE (Analog Front End) component may beused between the digital image processor 73 and the sensor 72. Such anAFE may be based on VSP2560 ‘CCD Analog Front End for Digital Cameras’from Texas Instruments Incorporated of Dallas Tex., U.S.A. The block 73further contains a digital image processor, which receives the digitaldata from the ATE, and processes this digital representation of theimage to handle various industry-standards, and to execute variouscomputations and algorithms. Preferably, additional image enhancementsmay be performed by the block 73 such as generating greater pixeldensity or adjusting color balance, contrast and luminance. Further, theblock 73 may perform other data management functions and processing onthe raw digital image data. Commonly, the timing relationship of thevertical/horizontal reference signals and the pixel clock are alsohandled in this block. Digital Media System-on-Chip device TMS320DM357from Texas Instruments Incorporated of Dallas Tex., U.S.A. is an exampleof a device implementing in a single chip (and associated circuitry)part or all of the image processor 73, part or all of the videocompressor 74 and part or all of transceiver 75. In addition to a lensor lens system, color filters may be placed between the imaging opticsand the photosensor array to achieve desired color manipulation.

The block 73 converts the raw data received from the photosensor array72 into a color-corrected image in a standard image file format. Thecamera 16 further comprises a connector 79 for connecting to the cable26. In order to transmit the digital image to the image processor 12 inthe control box 11 via cable 26 (which may contain a wired or non-wiredmedium), a transmitter or transceiver 75 is disposed between theconnector 79 and the image processor 73. The transceiver 75 alsoincludes isolation magnetic components (e.g. transformer-based),balancing, surge protection, and other suitable components required forproviding a proper and standard interface via a connector 79. In thecase of connecting to a wired medium, the connector 79 further containsprotection circuitry for accommodating transients, over-voltage andlightning, and any other protection means for reducing or eliminatingthe damage from an unwanted signal over the wired medium. A band passfilter may also be used for passing only the required communicationsignals, and rejecting or stopping other signals in the described path.A transformer may be used for isolating and reducing common-modeinterferences. Further a wiring driver and wiring receivers may be usedin order to transmit and receive the appropriate level of signal to andfrom the wired medium. An equalizer may also be used in order tocompensate for any frequency dependent characteristics of the wiredmedium. Further, the communication over the cable 26 can bebi-directional, such as half-duplex or full-duplex, or one-way, whereinthe camera 16 only transmits the image to the control box 11.

A controller 77, located within the camera module 16, may be based on adiscrete logic or an integrated device, such as a processor,microprocessor or microcomputer, and may include a general-purposedevice or may be a special purpose processing device, such as an ASIC,PAL, PLA, PLD, Field Programmable Gate Array (FPGA), Gate Array, orother customized or programmable device. In the case of a programmabledevice as well as in other implementations, a memory is required. Thecontroller 77 commonly includes a memory that may include a static RAM(random Access Memory), dynamic RAM, flash memory, ROM (Read OnlyMemory), or any other data storage medium. The memory may include data,programs, and/or instructions and any other software or firmwareexecutable by the processor. The control logic can be implemented inhardware or in software, such as a firmware stored in the memory. Thecontroller 77 controls and monitors the device operation, such asinitialization, configuration, interface and commands. The term“processor” is meant to include any integrated circuit or otherelectronic device (or collection of devices) capable of performing anoperation on at least one instruction including, without limitation,reduced instruction set core (RISC) processors, CISC microprocessors,microcontroller units (MCUs), CISC-based central processing units(CPUs), and digital signal processors (DSPs). The hardware of suchdevices may be integrated onto a single substrate (e.g., silicon “die”),or distributed among two or more substrates. Furthermore, variousfunctional aspects of the processor may be implemented solely assoftware or firmware associated with the processor.

Power to the digital camera module 16 is required for its describedfunctions such as for capturing, storing, manipulating, and transmittingthe image. A dedicated power source may be used such as a battery or adedicated connection to an external power source via connector 69. In apreferred embodiment, power is supplied from the control box 11 viacable 26, serving for both power and image transmitting. The powersupply 78 contains a DC/DC converter. In another embodiment, the powersupply 78 is power fed from the AC power supply via AC plug as connector69 and a cord, and thus may include an AC/DC converter, for convertingthe AC power (commonly 115VAC/60 Hz or 220VAC/50 Hz) into the requiredDC voltage or voltages. Such power supplies are known in the art andtypically involves converting 120 or 240 volt AC supplied by a powerutility company to a well-regulated lower voltage DC for electronicdevices. In one embodiment, power supply 78 is integrated into a singledevice or circuit, in order to share common circuits. Further, the powersupply 78 may include a boost converter, such as a buck boost converter,charge pump, inverter and regulators as known in the art, as requiredfor conversion of one form of electrical power to another desired formand voltage. While power supply 78 (either separated or integrated) canbe an integral part and housed within the camera enclosure, they may beenclosed as a separate housing connected via cable to the cameraassembly. For example, a small outlet plug-in step-down transformershape can be used (also known as wall-wart, “power brick”, “plug pack”,“plug-in adapter”, “adapter block”, “domestic mains adapter”, “poweradapter”, or AC adapter). Further, power supply 78 may be a linear orswitching type.

Various formats that can be used to represent the captured image areTIFF (Tagged Image File Format), RAW format, AVI, DV, MOV, WMV, MP4, DCF(Design Rule for Camera Format), ITU-T H.261, ITU-T H.263, ITU-T H.264,ITU-T CCIR 601, ASF, Exif (Exchangeable Image File Format), and DPOF(Digital Print Order Format) standards. In many cases, video data iscompressed before transmission, in order to allow its transmission overa reduced bandwidth transmission system. A video compressor 74 (or videoencoder) is shown in FIG. 7 disposed between the image processor 73 andthe transceiver 75, allowing for compression of the digital video signalbefore its transmission over the cable 26. In some cases compressionwill not be required, hence obviating the need for such compressor 74.Such compression can be lossy or lossless types. Common compressionalgorithms are JPEG (Joint Photographic Experts Group) and MPEG (MovingPicture Experts Group). The above and other image or video compressiontechniques can make use of intraframe compression commonly based onregistering the differences between part of single frame or a singleimage. Interframe compression can further be used for video streams,based on registering differences between frames. Other examples of imageprocessing include run length encoding and delta modulation. Further,the image can be dynamically dithered to allow the displayed image toappear to have higher resolution and quality.

Single lens or a lens array 71 is positioned to collect optical energyrepresentative of a subject or a scenery, and to focus the opticalenergy onto the photosensor array 72. Commonly, the photosensor array 72is a matrix of photosensitive pixels, which generates an electric signalthat is representative of the optical energy that is directed at thepixel by the imaging optics.

A prior art example of a portable electronic camera connectable to acomputer is disclosed in U.S. Pat. No. 5,402,170 to Parulski et al.entitled: “Hand-Manipulated Electronic Camera Tethered to a PersonalComputer”. A digital electronic camera which can accept various types ofinput/output cards or memory cards is disclosed in U.S. Pat. No.7,432,952 to Fukuoka entitled: “Digital Image Capturing Device having anInterface for Receiving a Control Program”, and the use of a disk driveassembly for transferring images out of an electronic camera isdisclosed in U.S. Pat. No. 5,138,459 to Roberts et al., entitled:“Electronic Still Video Camera with Direct Personal Computer (PC)Compatible Digital Format Output”, which are all incorporated in theirentirety for all purposes as if fully set forth herein. A camera withhuman face detection means is disclosed in U.S. Pat. No. 6,940,545 toRay et al., entitled: “Face Detecting Camera and Method”, which isincorporated in its entirety for all purposes as if fully set forthherein.

Face detection (also known as face localization) includes an algorithmsfor identifying a group of pixels within a digitally-acquired image thatrelates to the existence, locations and sizes of human faces. Commonface-detection algorithms focused on the detection of frontal humanfaces, and other algorithms attempt to solve the more general anddifficult problem of multi-view face detection. That is, the detectionof faces that are either rotated along the axis from the face to theobserver (in-plane rotation), or rotated along the vertical orleft-right axis (out-of-plane rotation), or both. Various face detectiontechniques and devices (e.g. cameras) having face detection features aredisclosed in U.S. Pats. RE33682, RE31370, U.S. Pat. Nos. 4,047,187,4,317,991, 4,367,027, 4,638,364, 5,291,234, 5,386,103, 5,488,429,5,638,136, 5,642,431, 5,710,833, 5,724,456, 5,781,650, 5,812,193,5,818,975, 5,835,616, 5,870,138, 5,978,519, 5,987,154, 5,991,456,6,097,470, 6,101,271, 6,128,397, 6,148,092, 6,151,073, 6,188,777,6,192,149, 6,249,315, 6,263,113, 6,268,939, 6,282,317, 6,301,370,6,332,033, 6,393,148, 6,404,900, 6,407,777, 6,421,468, 6,438,264,6,456,732, 6,459,436, 6,473,199, 6,501,857, 6,504,942, 6,504,951,6,516,154, 6,526,161, 6,940,545, 7,110,575, 7,315,630, 7,317,815,7,466,844, 7,466,866 and 7,508,961, which are all incorporated in itsentirety for all purposes as if fully set forth herein.

The electrical form of the image captured by the camera 16 is receivedvia cable 26 at the image processor 12 in control box 11. The imageprocessor 12 performs face detection algorithms on the received image,to determine if there is a face (or plurality of faces) in the capturedimage, and the location of each detected face in the captured view. Theimage processor 12 transmits the processing results to controller 13 vialink 25. The image processor 12 may be based on a discrete logic or anintegrated device, such as a processor, microprocessor or microcomputer,and may include a general-purpose device or may be a special purposeprocessing device, such as an ASIC, PAL, PLA, PLD, Field ProgrammableGate Array (FPGA), Gate Array, or other customized or programmabledevice. In the case of a programmable device as well as in otherimplementations, a memory is required. The image processor 12 commonlyincludes a memory that may include a static RAM (random Access Memory),dynamic RAM, flash memory, ROM (Read Only Memory), or any other datastorage medium. The memory may include data, programs, and/orinstructions and any other software or firmware executable by theprocessor. The control logic can be implemented in hardware or insoftware, such as a firmware stored in the memory. The term “processor”is meant to include any integrated circuit or other electronic device(or collection of devices) capable of performing an operation on atleast one instruction including, without limitation, reduced instructionset core (RISC) processors, CISC microprocessors, microcontroller units(MCUs), CISC-based central processing units (CPUs), and digital signalprocessors (DSPs). The hardware of such devices may be integrated onto asingle substrate (e.g., silicon “die”), or distributed among two or moresubstrates. Furthermore, various functional aspects of the processor maybe implemented solely as software or firmware associated with theprocessor.

The controller 13 controls and monitors the device operation, such asinitialization, configuration, interface and commands. The controller13, located within the control box 11, may be based on a discrete logicor an integrated device, such as a processor, microprocessor ormicrocomputer, and may include a general-purpose device or may be aspecial purpose processing device, such as an ASIC, PAL, PLA, PLD, FieldProgrammable Gate Array (FPGA), Gate Array, or other customized orprogrammable device. In the case of a programmable device as well as inother implementations, a memory is required. The controller 13 commonlyincludes a memory that may include a static RAM (random Access Memory),dynamic RAM, flash memory, ROM (Read Only Memory), or any other datastorage medium. The memory may include data, programs, and/orinstructions and any other software or firmware executable by theprocessor. The control logic can be implemented in hardware or insoftware, such as a firmware stored in the memory. The controller 13controls and monitors the device operation, such as initialization,configuration, interface and commands.

During operation, the image captured by camera 16 is processed for facedetection by image processor 12. The results of face detectionprocessing, such as the existence of a face in the image, the number ofdetected faces and the location of the detected face are provided to thecontroller 13 via link 25. The controller 13 in turn provides commandsto the motor control 14 via link 24, for rotating the motor 15, which inturn rotates the display 18 attached thereto.

The system operation is described in flow chart 100 in FIG. 10, and willbe exampled with regard to FIGS. 11 to 14, showing a living room whereina person 114 is sitting on a sofa 113 and watching the display 18 (e.g.a flat screen television set) being part of a system 10 according to theinvention. FIG. 11 shows a perspective rear view 110 of the display 18(and a perspective front view of the person 114 sitting on the sofa113). FIG. 12 shows a perspective front view 120 of the display 18 (anda perspective rear view of the person 114 sitting on the sofa 113). FIG.13 shows a side view 130 and FIG. 14 is a top view of the system 10,person 114 and the sofa 113. Similarly, FIG. 16 shows a top view 160 ofthe room wherein no person is present in the room.

As shown in top view 140 in FIG. 14, the sofa 113 is centeredsubstantially vertically directly across from the display 118, as shownin the imaginary line of sight 141 connecting the sofa 113 center to thedisplay 18 center. Hence, the center place on the sofa 113 is theoptimal seating place, providing best visibility of the image on thedisplay 18. However, as shown in FIGS. 11 to 14, the person 114 issitting in a side seat of the sofa 113, thus using the line of sight 142to the display 18, which is deviated from the optimal line 141.

The flow chart 100 is executed by the system and controlled and managedby the software (or firmware) in controller 13 in the control box 11.The system activation starts at step ‘Start’ 101. Next in step ‘ImageCapture’ 102, the camera 16 is operated to capture a single ‘still’frame or a video including streaming of frame. The image captured istransmitted from the camera 16 to the image processor 12 within thecontrol box 11 via communication link 26, which may be a cable. FIG. 15shows an example of an image 150 that is captured by the camera 16,featuring the person 114 sitting on the sofa 113.

The captured image (such as image 150) is then process by the imageprocessor 12 in ‘face detection’ step 103. A face detection algorithm isexecuted on the image captured, and the count of detected faces ischecked in ‘Faces Count’ step 104. If human faces are detected in step103 by the image processor 12, the detected face location is determined,such as rectangular 152 relating to person 113 face detected in image150. In some cases, no person is present in the room, as shown in topview 160 in FIG. 16. In such a case, the image captured is shown animage 170 in FIG. 17, wherein only the sofa 113 is present, the imagecaptured. If no human faces are detected, either due to the fact that nohumans are present in the image or they are not watching at the display18 or camera 16, then it is assumed that no humans are currentlywatching the display 18 (Faces Count equal zero). In this case, thesystem wait a predetermined period TIMER in ‘wait Time’ step 105 duringwhich the system is idle, and afterwards the system resumes to itsoperation from the start in step 102. The TIMER period can be in theorder of seconds (e.g. 1 to 10 seconds), dozens of seconds (e.g. 30 to60 seconds), minutes (e.g. 1 to 10 minutes), dozens of minutes (e.g. 30to 60 minutes) or hours (e.g. 1 to 10 hours).

In the case a single human face is detected in step 103 (such as facedetection 152 in image 150), the horizontal location of the face centeris determined by the image processor 12, shown as dashed line 153 inFIG. 15. The dashed vertical line 153 is calculated to be at thedetected face 152 center.

In the next step ‘Face Location Deviation’ 106, the distance deviationbetween the image center represented by the imaginary dashed line 151horizontally centered in the image, and the detected face 152 centerlocation line 153 is calculated (shown as the deviation line 154 in FIG.15). This distance represents the deviation of the person location(particularly its face location) from the optimal viewing pointrepresented by the image center line 151.

Next, the deviation is checked in ‘Deviation <Delta’ step 107. In thecase there is no deviation (Deviation=0), or if the deviation value islower from a pre-set limit value, this means that the person watchingthe screen of display 18 is exactly or substantially locate in the bestviewing position. Hence, there is no need for any improvement of theviewing angle, and the system reverts to idling in step 105. Such a caseis described in FIG. 18 showing a top view 180 of a room wherein theperson 114 watching the display 18 is sitting in the center seat of thesofa 113 and thus is located directly across the system having anoptimum display 18 view. The image captures in such a case is shown asimage 190 in FIG. 19, showing that the image horizontal center line 151coincides with the detected face 152 center line 153, hence thedeviation 154 is zero. In the case the deviation is above a pre-setvalue, the controller 13 operates in step ‘Display Rotation’ 111 torectify the situation by ordering the motor 15 (via the motor controller14) to rotate in a direction that reduce the deviation. In the exampleof image 150 in FIG. 15, the person is located to the left side of theimage, when viewed from the camera 16 point of view. In this case, themotor 15 with rotate the display counter-clockwise when looked from top,bringing the display 18 to the viewer person 113 line of sight.

In one embodiment, in the case wherein it is determined that therotation of the motor 15 is required to correct the line-of-sightdeviation 154, the motor 15 will rotate a pre-set angular movement tothe required direction, regardless of the measured deviation 154. Forexample, an angular shift of 1 degree (1°) can be used. The rotationwill be clockwise or counter-clockwise depending upon the deviation sideversus the center line 151. Similarly, other angular shifts such as 2degrees (2°), 5 degrees (5°) or 10 degrees (10°) may be used. In anotherembodiment, the motor 15 angular shift is dependent upon the actualmeasured deviation 154. Large deviation will result in a larger shift,while small deviation value will result in a smaller angular shift. Forexample, the angular rotation can be proportional to the value of thedeviation 154.

After executing the required angular shift in ‘Display Rotation’ step111, the system is idling for a period of TIMER in ‘Wait Time’ step 105before another correction cycle starts (a cycle comprising all therequired steps from ‘Image Capture’ step 102 to completing a DisplayRotation' step 111). The case may be wherein few cycles will be requiredbefore the deviation is fully corrected and the system is idling aftergetting into zero (or substantially small) deviation. For example, inthe case of a fixed angular rotation of 2 degrees (2°) is performed in‘Display Rotation’ step 111, the system will require 5 (five) cycles tocompensate for an angular deviation of 10 degrees (10°). Further,continuous operation also allows for continuous correction of thedeviation, which may result due to the shift of the person position inthe room. For example, in the case the person 114 moves to another seaton the sofa 113, one or more cycles may be required to adjust the systemto the new location of the person. Similarly, adding watching personscan also require system adjustments will be described hereafter.

The continuous operation of the system as shown in flow chart 100effectively implement a feedback control loop, wherein the camera 16acts as a sensor for obtaining the deviation 154 and the motor 15 servesas an actuator, and the control loop (which may be a linear controlloop) tries to regulate in order to minimize the value of the deviation154 (set point zero for the measured deviation 154). Linear control mayalso be used for such negative feedback system. Such a system can useproportional-only control loop, however PID (Proportional, Integral,Derivative) control known in the art commonly provides better controlresults.

The system steady-state situation after completing all required cycles(one or more) to align the line-of-sight to its optimal position isdescribed with regard to FIGS. 20 to 24, showing a living room wherein aperson 114 is sitting on a sofa 113 and watching the display 18 (e.g. aflat screen television set) being part of a system 10 according to theinvention. FIG. 20 shows a top view 200 wherein the display 18 is shownfacing directly the person 114 on sofa 113, as shown in the dashedline-of-sight 201. FIG. 22 shows a perspective front view 210 of thedisplay 18 (and a perspective rear view of the person 114 sitting on thesofa 113). FIG. 22 shows a side view 220 and FIG. 23 is anotherperspective front view of the system 10 (and a perspective rear view ofthe person 114 sitting on the sofa 113).

FIG. 24 shows the image 240 captured by the camera 16 at this steadystate. The face detected 152 center line 153 coincides with the imagecenter line 151, resulting deviation distance of zero (actually orpractically less than Delta).

In some cases, multiple persons may be watching the display 18 at thesame time. Such scenario is shown in a top view 250 in FIG. 25. Anadditional person 114 b is shown sitting in the sofa 113 center seat,added to the person 114 a sitting on the sofa 113 side-seat as describedabove. In such a situation, the optimal viewing angle is different foreach person being in different location. The best solution is to directthe display 18 towards the center between the persons 114 a and 144 b,such that each will enjoy a low deviation in a fair partition. Handlingfew detected faces is handled in the left side of flow chart 100,consisting of ‘Average Location Calculation’ step 108 and ‘averageLocation Deviation’ step 109.

Image 260 shown in FIG. 26 shows the captured image in the camera 16 inthe case shown in FIG. 26. The image processor 12, using face detectionalgorithms, identifies the two faces of persons 114 a and 144 b by therespective face frames 152 a and 152 b, and associates an horizontallocation lines 153 a and 153 b respectively, similar to above discussionrelating to FIG. 15. Next, as part of ‘Average Location Calculation’step 108 in flow-chart 100, the average face location is calculated.Such average horizontal location 271 is shown as part of image 270 inFIG. 27. The lines 153 a and 153 b, representing the respective locationof the detected faces 152 a and 152 b, are equally distant from theaverage line 271, as shown by distances 272 a and 272 b respectively.The average location 271 is used, as a substitute to the location line153 shown in FIG. 15, as the means for calculating the deviation fromthe image center line 151. The deviation 154 between the image centerline 151 and the average line 271 will be calculated in ‘AverageLocation deviation’ step 109.

Based on the deviation value 154 (derived from the average position ofboth faces), the system will rotate the display 18 such that thedeviation will be minimized as described above. The system steady-statesituation after completing all required cycles (one or more) to alignthe line-of-sight to its optimal position is described with regard toFIG. 29, showing a living room wherein the two persons 114 a and 114 bare sitting on a sofa 113 and watching the display 18 (e.g. a flatscreen television set) being part of a system 10 according to theinvention. FIG. 29 shows a top view 290 wherein the display 18 is shownfacing directly the middle point between the persons 114 a and 144 b onsofa 113, as shown in the dashed line-of-sight 291. The image capturedby the camera 16 in this situation is shown as image 280 in FIG. 28,wherein the average line 271 and the image center line 151 coincides,resulting in zero deviation value.

While the invention has been exampled above with regard to a singlemotor and rotating the display 18 in a single axis, being the horizontalaxis, it is the invention may equally apply to rotating the display 18in the vertical axis only. In such a scenario, the display 18 will beinclined as required to ensure direct line of sight for optimum view inthe vertical axis.

Further, the invention can be applied to rotate the display 18 in boththe horizontal and vertical axes, thus allowing for better and optimalviewing. A block diagram of such a system 300 is shown in FIG. 30, usinga two-axes control box 301. The horizontal rotation is using thehorizontal motor (H. Motor) controller 14 a which receives commands fromthe controller 13 via the connection 24 a, and controls horizontal motor15 a via connection 23 a, which axis is in turn mechanically coupled tothe display 18 for horizontal rotation. This horizontal handlingcorresponds to system 10 shown in FIG. 1, showing the horizontal motor(H. Motor) controller 14 which receives commands from the controller 13via the connection 24, and controls horizontal motor 15 via connection23, which axis 17 a is in turn mechanically coupled to the display 18for horizontal rotation. A set of a vertical motor (V. Motor) controller14 b and a vertical motor 15 b are added to system 10 for inclining thedisplay (in the vertical axis) as required. The vertical rotation isusing the vertical motor (V. Motor) controller 14 b which receivescommands from the controller 13 via the connection 24 b, and controlshorizontal motor 15 b via connection 23 b, which axis 17 b is in turnmechanically coupled to the display 18 for vertical rotation.

A pictorial exemplary system is shown in FIGS. 31 to 34, wherein apictorial front perspective view 310 of the system having two axes lineof sight correction is shown in FIG. 31, a rear perspective view 320 isshown in FIG. 32, a side view 330 is shown in FIG. 33 and an anotherperspective side view 340 is shown in FIG. 34. A control box 301 isshown supporting operation in both vertical and horizontal planes.Horizontal motor 15 a is shown attached to pedestal 27 via axis 17 a,for horizontal rotating of the display 18, as described above relatingto FIGS. 2 to 6. In order to allow rotation also in the vertical plane,a second pedestal 302 is added attached to the former pedestal 28. Thesecond pedestal 302 serves a basis to the vertical motor 15 b, which isattached to the display 18 via the axis 17 b. In operation, verticalmotor 15 b rotates its axis 17 b and the display 18 attached theretothus inclining the display 18, hence controlling its vertical line ofsight. FIG. 3 shows a display 18 shifted from its original inclination(shown as dashed frame 331) to a reclining position. Similarly, areclining display 18 is shown in FIG. 34.

The operation of such two-axes system in the horizontal plane will besimilar to the above operation described in FIG. 10 and the appendedFIGS. 11 to 29, wherein the horizontal rotation required in affected bythe H. Motor 14 a via its axis 17 a. In parallel, and simultaneouslywith the horizontal loop, a similar vertical control loop is executed.He image processing in case of correcting two planes is exampled withregard to image captured 350 shown in FIG. 35 (based on FIG. 15). In the‘Face Location deviation’ step 106 executed as part of flow chart 100executed by the image processor 12, not only the horizontal deviation154 is estimated, but rather the vertical deviation 352 is calculated aswell. Similar to the horizontal calculation above regarding thehorizontal deviation 154, the vertical deviation 352 is the differencebetween the image horizontal center line 351 and the vertical position353 of the detected face 152. Similar to above description, the controlloop is operative to lower the vertical deviation 352 to a minimum valueor zero, thus aligning the viewer line of sight with the plane of thedisplay 18 offering optimal viewing experience.

While the invention has been exampled above with regard to a singlemotor and rotating the display 18 in a single axis, being the horizontalaxis, and with regard to including a second motor for rotating thedisplay 18 in both horizontal and vertical planes, the invention mayequally apply to rotating the display 18 in the vertical axis only. Insuch a scenario, the display 18 will be inclined as required to ensuredirect line of sight for optimum view only in the vertical axis. In thiscase, the system 300 shown in FIG. 30 will use only the vertical motor15 b and its controller 14 b, and the horizontal components (such asmotor 15 a and controller 14 a) may be obviated.

While the invention has been exampled above with regard to a specificpartition of the system components into various enclosures, theinvention may equally apply to any other partition. For example, thecamera 16 has been described above having a dedicated casing housingonly the camera related hardware. However, the camera may as well beintegrated into the control box 301 (or control box 11), obviating theneed for additional enclosure and cable 26. The integration may be justhousing of the camera 16 in the same enclosure, or may share commonhardware such as power supply, control lines and mechanical fixing. Inone embodiment, the camera 16 is integrated with the display 18 orfixedly attached thereto. One advantage of such solution is that manydisplays already include a build-in camera for video conferencing (suchas laptops). In another embodiment, the image processor 12 is integratedinto the camera 16 enclosure.

In one example, the motor controller 14 a is integrated within thecasing of the motor 15 a. Similarly, the motor controller 14 b isintegrated within the casing of the motor 15 b. Further, the motor 15 a(and/or the motor 15 b) may be integrated or fixedly combined with thedisplay 18. In another embodiment, the control box 301 (or control box11) may be enclosed (in part or in full) in the camera 16 enclosure orwith the motor 15 a (or motor 15 b). Alternatively, the control box 301may be fully integrated within the display 18 housing.

While the invention has been exampled above with regard to using theface detection means in order to mechanically move the display 18 basedon the location of the detected face or faces, the invention may equallyapply to using the face detection for other controls of the display 18or other devices.

In one exemplary embodiment, the face detection mechanism is used forturning the display ON and OFF. The detection of a human face in thecaptured image is serving as an indication that at least one person iswatching the screen. In the case no faces are detected, the systemassumes that no one is watching the screen, thus shutting off thedisplay. This provides the benefit of not consuming power when notrequired, thus saving energy and the associated electricity expenses.Further, since electrical systems in general and displays in particularhave a limited life span, such shutdown increases the usage of thescreen and its operation life by saving wear and tear of the screen whenits operation is not required. A block diagram 360 of such a system isshown in FIG. 36, based on a control box 361 (substituting the controlbox 11 described above). Similar to system 10 described above the system360 comprises a camera 16, feeding its captured image to the imageprocessor 12 via communication link 26. The image processor 12 uses facedetection image processing algorithms, detect the existence of humanfaces in the image captured, and notify the controller 363 viaconnection 25. Controller 363 may be identical or similar to controller13 above. The display 18 is powered from the AC plug 21 via controlledon/off switch 362 and power cable 365, which is controlled by thecontroller 363 via the control connection 364. Hence, the controller 363may turn the display 18 on and off by activating switch 362. The switch362 may be implemented by relay contacts, wherein line 364 is a controlsignal used to energize and de-energize the coil of the relay, or may beimplemented using solid state circuitry as known in the art.

The system operation is exampled as flow chart 400 in FIG. 40. The flowchart 400 execution is managed, controlled and handled by the controller363 in control box 361. Upon system activation in Start step 401, thecontroller 363 provides an activation control signal 361 to the switch362, commanding it to close and pass the AC power from the AC plug 21 tothe display 18, thus turning the display 18 on. Then ‘Start Timer1’ step403 is executed, wherein a timer having a pre set period of time(Timer1) starts to count the elapsing time, counting down from thespecified time interval to zero. ‘Face Detected’ Step 404 is similar (orthe same) as ‘Face detection’ step 103, wherein the image processor 12analyzes the captured image and notify the existence of a detected faceto the controller 363. If a face (or multiple faces) is detected, theTimer1 is reset and start its count again in ‘Start Timer1’ step 403.Hence, as long as a face is detected, the system will be in thecontinuously performing the loop of steps ‘Start Timer1’ step 403 and‘Face Detected’ step 404, wherein the display 18 is in ON state as itcontinues to receive power via switch 362. In the case no face isdetected by the image processor 12, the time elapsed is checked inTimer1 in ‘Timer 1 expired’ step 405. As long as Timer has not elapsed,the system will continue to check if a face has been detected in ‘FaceDetected’ step 404, and will reset the timer upon such detection. Onlyif throughout the Timer1 operation period no face has been detected, thepower to the display 18 will be turned off in ‘Turn OFF’ step 406, byopening the switch 362 contacts and thus de-energizing the display 18.This mechanism allows for secure shutting off of the display 18, andwill obviate the false detection such as the case of turning the display18 off due to intermittent missing of a face detection occurrence orafter too short period of lacking of face detection, thus adding to thesystem reliability.

After turning off the power to the display 18 in ‘Turn OFF’ step 406, asecond timer (Timer2) is initiated in ‘Start Timer2’ step 407. Timer2 ispre set to a period which may be similar or distinct from the period setfor Timer 1. Further, the two timers can be implemented using the samehardware or software/firmware, or sharing part of the means required forthese timers. Then a face detection mechanism is executed in ‘faceDetected’ step 408 (similar to the Face detected step 404). If no faceis detected in ‘Face detected’ step 408, the Timer2 is restarted itscount. As long as no face is detected, it is assumed that no person isviewing the display 18 hence no power is supplied to the display 18rendering it turned off. Similar to the action of ‘Timer1 expired’ step405, ‘Timer2 expired’ step 409 assures that a face needs to be detectedfor at least the period set in Timer2. Upon such occurrence, it isassumed that a person is actually looking at the display 18, and thusthe power to the display 18 is resumed in ‘turn ON’ step 402. Thismechanism provides a reliable and stable operation promising that noaction will be taken before assuring that the face detection isconsistent and stable.

Each of said timers period can be in the order of seconds (e.g. 1 to 10seconds), dozens of seconds (e.g. 30 to 60 seconds), minutes (e.g. 1 to10 minutes), dozens of minutes (e.g. 30 to 60 minutes) or hours (e.g. 1to 10 hours). The timers period can be the same, substantially similaror having substantial differences periods.

While the invention has been exampled above with regard to a specificpartition of the system components into various enclosures, theinvention may equally apply to any other partition. For example, thecamera 16 has been described above having a dedicated casing housingonly the camera related hardware. However, the camera may as well beintegrated into the control box 361 obviating the need for additionalenclosure and cable 26. The integration may be just housing of thecamera 16 in the same enclosure, or may share common hardware such aspower supply, control lines and mechanical fixing. In one embodiment,the camera 16 is integrated with the display 18 or fixedly attachedthereto. One advantage of such solution is that many displays alreadyinclude a build-in camera for video conferencing (such as laptops). Inanother embodiment, the image processor 12 is integrated into the camera16 enclosure. Alternatively, the control box 361 may be fully integratedwithin the display 18 housing.

System 410 shown in FIG. 41 is a block diagram of a system according tothe invention which uses the face detection functionality for bothobtaining a better viewing of the display 18 as described above (forexample with regard to FIGS. 1 to 35), and for controlling the screenfunctions (e.g. turning on/off as exampled in FIGS. 36 to 40). The blockdiagram 300 shown in FIG. 30 is combined with the system 360 shown inFIG. 36, making an efficient use of the common components such as camera16 and power supply 19. Controller 412 combines the functions ofcontroller 363 with the functions of controller 13, and the control box411 is used to house all the relevant components as shown in FIG. 41.

While the invention has been exampled above in FIG. 41 with regard toturning the display 18 on and off by connecting or disconnecting thepower to the display 18 (allowing the usage with any type of a display18), the invention may equally apply to the case wherein the controlledfunctionality is internal to the display 18. For example, only the powerto the screen itself (e.g. the LEDs—Light Emitting Diodes illuminatingthe screen) may be stopped, thus blanking the display. Alternatively,the display 18 may be commended to shift to a shutdown mode, similar tothe mode used upon turning off a display by a remote control. Further,excessive power on/off actions (for the whole display 18 system) mayreduce its operative life span. An example of such a system 420 is shownin FIG. 42. The switch 362 is internal to the display 18 and controlledvia connection 422 connected to a connector 423, and effect only part ofthe display 18 functions, such as only excessive power consumingcircuits or limited life span components. Upon decision to turn off, thecontrol box 421 comprises a connector 424, used for connecting to thedisplay 18 via cable 425. Thus, the controller 363 extends its controlport 364 to manage and control the switch 362 internal to the display18.

A pictorial perspective front view 370 of such a system is shown in FIG.37, and a pictorial perspective rear view 380 of such a system is shownin FIG. 38. These views are similar respectively to views 20 and 30shown in FIGS. 2 and 3 respectively, where the motor 15 (and itsassociated parts such as axis 17) is not used. The display power cord365 is shown connecting the display 18 to the control box 360 forreceiving power therefrom via the switch 362.

While the invention has been exampled above with regard to the display18 placed on a horizontal plane such as drawers chest 27, the inventionmay equally apply to other positioning means such as wall (or othervertical plane) mounting. An example of a wall mounting system is shownin view 390 in FIG. 39, wherein a wall mounting fixture 391 is used,including a bracket for wall mounting.

While the invention has been exampled above with regard to using facedetection to control various devices, the invention may equally apply tothe case wherein the system is using detection relating to other humanorgans. Further, the invention may equally apply to the case whereinactive action from the person involved is detected such as a gesturemade with a part of the human body, and detected by the image processor12. For example, nodding, bobbling or shaking can be used as indicationto be detected by the image processor and used for various remotecontrol applications.

In one example, hand gesture is used for signaling the system, asexampled in FIGS. 43 to 46. FIG. 30 shows a perspective rear view 430,FIG. 44 shows a side view 440 and FIG. 45 shows a top view 450. As shownin the views in these figures, the person 114 on the sofa 113 signal thesystem by an hand gesture, consisting of extracting only the indexfinger, thus ‘pointing’ to the ceiling of the room. While the abovedescription referred to the image processor 12 performing face detectionalgorithms such as in ‘Face Detection’ step 103 in flow chart 100 (and‘Face Detected’ steps 404 and 408 in flow chart 400), the imageprocessor 12 executes ‘hand gesture detection’ algorithms in order todetect the hand gesture made by the person 114. The analysis results areexampled in the image captured 460 in FIG. 46, wherein the hand 462 (orthe palm) is detected as shown in the dashed rectangular 461, and theindex finger 463 is detected and identified as pointing upwards.

Similarly, other hand gestures may be signaled and detected (andidentified as such), involving extending of all or part of the fingers.For example, image view 470 shows three fingers 464 raised (the index,middle and ring fingers, added to the thumb). Similarly, image view 480in FIG. 48 detects a person extracting all his/her fingers 465, andimage view 490 in FIG. 49 shows a case wherein only an index finger 466is raised (added to the thumb). Two fingers 467 (index and middle) and athumb are shown detected in the hand detected 461 as part of image 500in FIG. 50.

In one embodiment, the hand gesture is used to control the display 18 asa substitute to the face detection described above. For example, thecontrol may involve turning the display 18 on and off as described aboverelating to FIGS. 36 to 42, wherein the image processor 12 is notifyingthe controller 412 regarding the detection of a hand gesture. Operationof such a system is described in flow chart 510 shown in FIG. 51, basedon the flow chart 400 shown in FIG. 40 and described above. The ‘FaceDetected’ steps 404 and 408 are respectively replaced with Hand GestureDetected' steps 511 and 512, wherein the ‘Yes’ branch related to theevent when a hand gesture is detected and identified by the system.

Remote controls are known in the art as electronic devices used for theremote operation of equipment. Wired or wireless remote control devicesincluding Infra-Red (IR) or RF transmitter for remotely operating ACpowered electrical appliances such as television receivers, homeheaters, air conditioners, motorized curtains, lighting and otherelectrical appliances in homes, apartments, offices and buildings ingeneral are switched on and off by a one way control or command signal.In most cases, the person operating the remote control device verifyingthe on or off status of the operated device by visual means, such as theTV is on, or the lights are off, or the air-condition unit is activatedor not, by being at the site of the operated appliance. Commonly, remotecontrols are Consumer IR devices used to issue commands from a distanceto televisions or other consumer electronics such as stereo systems DVDplayers and dimmers. Remote controls for these devices are usually smallwireless handheld objects with an array of buttons for adjusting varioussettings such as television channel, track number, contrast, brightnessand volume. In fact, for the majority of modern devices with this kindof control, the remote contains all the function controls while thecontrolled device itself only has a handful of essential primarycontrols.

Using face detection or hand gesture detection can replace part of orall the functions of a remote control unit, thus obviating the need forusing such additional and dedicated device for control. In oneembodiment, the system is used for turning on and off a specificfunction in the controlled device, or in general switching from onestate to the other of two states. In the example of a display 18 beingcontrolled (e.g. television set), the function controlled may be turningthe display on and off by supplying or disconnected power to the display(e.g. as disclosed in FIG. 36), a ‘mute’ function or a‘pause’/‘continue’ command to a DVD player. Such system operation may bebased on the flow chart 520 shown in FIG. 52, wherein the ‘Turn ON’ step402 and the ‘Turn OFF’ step 406 are substituted with the ‘Turn FunctionON’ step 521 and ‘Turn Function OFF’ step 522. The ‘Turn Function ON’step 521 is executed after the hand gesture is detected in ‘Hand GestureDetected’ step 511 for at least the period Timer1, and The ‘TurnFunction OFF’ step 522 is executed after the hand gesture is detected in‘Hand Gesture Detected’ step 407 for at least the period Timer2. In the‘Turn Function ON’ step 521 the function commanded (e.g. ‘mute’) isactivated (e.g. power turned on in the case of on/off control) orswitched to a first state (out of two states available), while in the‘Turn Function OFF’ step 522 the function commanded (e.g. ‘mute’) isdeactivated (e.g. power turned off in the case of on/off control) orswitched to the other state (out of two states available). In the casewherein more than two states are available in the involved function,such as television channels wherein multiple channels are available tochoose from, or in the case of a track number in a DVD player, andvolume having continuous or multiple discrete steps, the hand gesturecan be used to signal a single step of the function. For example, eachtime a detection of a hand gesture occurs may signal to shift to thenext television channel, to the track number or to the next volumelevel. In such control scheme, the ‘Turn Function ON’ step 521 (or the‘Turn Function OFF’ step 522 or both steps) activates the controlledunit to shift to the next step or level out of the multiple stepsrelating to the required function.

In one embodiment only a single hand gesture can be detected. Forexample, the system may only detect the hand gesture involving extendingonly the index finger as shown in FIGS. 43 to 46. Such system may usesimple image processor 12 since only a single object needs to bedetected, and such detection of the hand gesture will be detected in‘Hand detection Detected’ steps 511 and 512 in flow chart 520. Thedetected hand gesture may be used for a single activation (ordeactivation) of a function. Alternatively, the hand gesture may be usedto continuously toggle between activation and deactivation of afunction, wherein each such new detection of a hand gesture results inswitching from a state to the other (or shifting to the next level orstep), as described in flow chart 520 in FIG. 52.

In another embodiment, multiple hand gestures can be detected andidentified by the image processor 12. In this case, separate handgestures may be used for activation or deactivation of a function. Forexample, the hand gesture of ‘pointing up’ shown in FIGS. 43 to 46 canbe detected and identified, together with the ‘all fingers up’ gestureshown in view 480 in FIG. 48. For example, the ‘pointing up’ gesturewill be detected in ‘Hand Gesture Detected’ step 511 in flow chart 520and will cause to activate the function in ‘Turn Function ON’ step 521,while the ‘all fingers up’ gesture will be detected in ‘Hand GestureDetected’ step 512 in flow chart 520 and will cause to deactivate thefunction in ‘Turn Function OFF’ step 522. Similarly, one hand gesturemay cause a multiple states function (such as television channelselection) to shift upwards while the other hand gesture may results inshifting downwards. For example, assuming the television set iscurrently set to channel 15, one gesture shifts to channel 16('upwards'), while the other shifts to channel 14 ‘downwards’).Similarly, one type of hand gesture detected may affect increasing thevolume for a louder result, while the other will lower the volume tomore silent performance.

While the invention has been exampled above with regard to using handgestures for a single function control, the invention may equally applyto the case wherein multiple types of hand gestures will be used tocontrol multiple functions. For example, each hand gesture may be usedto control a single function, such as one hand gesture for ‘mute’, onefor ‘volume’ and one for turning the television on and off.

In one embodiment, the image processor 12 is capable of detecting bothhand gestures and human face. Such capability can be used in order toincrease the reliability of the hand gesture and to minimize false handgesture detection by searching for hand gesture in the image only if aface is detected in that image, since it is assumed that the handgesture is signaled by a person viewing the display 18, and thus his/herface are captured in the camera image. Hence, items which may be falselyidentified as a hand gesture being of similar shape, will not beconsidered and thus will not be identified as a hand gesture. Further,since the location of the face and the hand of a person are related,this can be further used to improve the system performance, by searchingand applying the algorithms for detecting hand gestures only in adefined location based on the detected face location. An example isshown in image 530 shown in FIG. 53, based on image 460 in FIG. 46. Theface detection mechanism will detect the face, as shown in the dashedrectangular 152 as described above. Assuming right-hand person, theprobable location of the signaling hand is expected (based on normalhuman dimensions) to be in the circled area 531, hence the hand gesturedetection should only search for a hand gesture in this area 531, savingprocessing time and minimizing false detection. Similarly, for aleft-handed person, the circle is placed to the person left side asshown in area 532 as part of image 540 in FIG. 54.

While the invention has been exampled above wherein the camera 16transmits the image to the image processor 12 via cable 26, theinvention may equally apply to the case wherein no such cable 26 is usedfor the communication. In one embodiment according to the invention, thecamera 16 is cordless, thus untethered and fully portable. In such aconfiguration, the camera 16 is preferably battery operated, thuspowered from an internal battery during operation without the need toconnect to a power source, such as AC power via a cord. Further, theimage is transmitted over the air using radio frequency, thus obviatingthe need for a cable or any other conductor connecting the camera 16 andthe control box. It is apparent the radio communication of the image canbe implemented also in the case of AC powered (via cable) camera.

Such a system 550 is shown in FIG. 55, adapter from system 410 in FIG.41. The transceiver 75 in camera 16 shown in FIG. 7 is substituted withwireless transceiver 551 b, connected to antenna 552 b. The wirelesstransceiver 551 b may be internally to the camera 16 enclosure or in aseparate housing. The control box 553 (adapted from control box 411 inFIG. 41) comprises a mating wireless transceiver 551 a connected toantenna 552 a. The image is transmitted from the camera 16 via thewireless transceiver 551 b and antenna 552 b over the air communication,to be received in the antenna 552 a and wireless transceiver 551 a.Hence, no cable is required between the camera 16 and the control box553, thus avoiding the inconvenience associated with such cord. Varioustypes of antennas 552 a and 552 b (or any other radio ports) can beused. Among these are PCB printed antennas, chip antennas, as well aspanel and dome antennas. Furthermore, the antennas may beomni-directional or directional. Typically, the antennas are coupledusing mating coaxial connectors, such as SMA, F-Type, N-Type and IPX,providing both the electrical connection as well as the mechanicalattachment. In many cases, the antenna connection allows for easydisconnection and connection by means of snapping or screwing.

Similarly, while the invention has been exampled above in system 420shown in FIG. 42 wherein the controlled display 18 is controlled viacable 425, the invention may equally apply to the case wherein no suchcable 425 is used for the control or communication link. In oneembodiment according to the invention, this control link is cordless,thus untethered and fully portable. Hence the control information istransmitted over the air using radio frequency, thus obviating the needfor a cable or any other conductor connecting the control box and thedisplay unit 18.

Such a system 560 is shown in FIG. 56, adapter from system 420 in FIG.42, wherein the connector 424 in the control box 421 is replaced with awireless transceiver 551 a in control box 561 (adapted from control box421 in FIG. 42), connected to antenna 552 a. A mating wirelesstransceiver 551 b connected to antenna 552 b are added to the display 18side, and may be separated or housed integrally within the display 18housing. The control information is transmitted from the controller 363in control box 561 via the wireless transceiver 551 a and antenna 552 aover the air communication, to be received in the antenna 552 b andwireless transceiver 551 b. Hence, no cable is required between thedisplay 18 and the control box 561, thus avoiding the inconvenienceassociated with such cord. Various types of antennas 552 a and 552 b (orany other radio ports) can be used. Among these are PCB printedantennas, chip antennas, as well as panel and dome antennas.Furthermore, the antennas may be omni-directional or directional.Typically, the antennas are coupled using mating coaxial connectors,such as SMA, F-Type, N-Type and IPX, providing both the electricalconnection as well as the mechanical attachment. In many cases, theantenna connection allows for easy disconnection and connection by meansof snapping or screwing.

Any short-range wireless communication based on free-air propagation canbe used for communication between the camera 16 and the control box 553in system 550, or between the control box 561 and the display 18 insystem 560. According to one embodiment of the invention, a WLANcommunication link is used to interconnect two or more isolated (W)PAN(Wireless Personal Area Network) systems. The reach of a PAN istypically a few meters, hence such networks are confined to a limitedspace, such as in-room communication. IEEE 802.15 is the working groupof the IEEE 802, which specializes in Wireless PAN (WPAN) standards.Non-limiting examples of WPAN systems include:

-   -   a. Bluetooth, which according to IEEE 802.15.1 standard, for        example, operates over license-free ISM band at 2.45 GHz. An        ad-hoc network of computing devices using Bluetooth technology        protocols is known as piconet.    -   b. Ultra-Wide-band (UWB), which according to the IEEE 802.15.3        standard, for example, uses a wavelet (sometimes referred to as        wireless USB). UWB or impulse radio transmitters emit short        pulses approaching a Gaussian monocycle with tightly controlled        pulse-to-pulse intervals.    -   c. ZigBee, which according to IEEE 802.15.4 standard, for        example, offers low data rate and low power consumption.    -   d. IEEE 802.11a, commonly considered as WLAN (Wireless Local        Area Network), but since it works in 5 GHz spectrum its reach is        considerably limited, thus IEEE802.11a may also be considered as        WPAN.

In addition to above technologies, proprietary networking schemes mayalso be used for interconnecting the units. Further, the system 553 canmake use of WLAN technologies. Currently widespread WLAN technologies(e.g. WiFi) are based on IEEE 802.11 and include IEEE 802.11b, whichdescribes a communication using the 2.4 GHz frequency band andsupporting a communication rate of 11 Mb/s, IEEE 802.11a uses the 5 GHzfrequency band to carry 54 MB/s and IEEE 802.11g uses the 2.4 GHz bandto support 54 Mb/s. Other technologies based on WPAN, WLAN, WMAN, WAN,BWA, LMDS, MMDS, WiMAX, HIPERMAN, IEEE802.16, Bluetooth, IEEE802.15,UWB, ZigBee, cellular, IEEE802.11 standards, GSM, GPRS, 2.5G, 3G, UMTS,DCS, PCS and CDMA may be equally used. Wireless and wired technologiesused for home networking can equally be used.

The Institute of Electrical and Electronic Engineers (IEEE) 802.11standard group, branded as WiFi by the Wi-Fi Alliance of Austin, Tex.,USA. IEEE 802.11b describes a communication using the 2.4 GHz frequencyband and supporting communication rate of 11 Mb/s, IEEE 802.11a uses the5 GHz frequency band to carry 54 MB/s and IEEE 802.11g uses the 2.4 GHzband to support 54 Mb/s. This is described in an Intel White Paperentitled “54 Mbps IEEE 802.11 Wireless LAN at 2.4 GHz”, and a chip-setis described in an Agere Systems White Paper entitled “802.11 WirelessChip Set Technology White Paper”, both of these documents beingincorporated herein by reference. Such a 802.11 supporting transceiverblock 551 a and 551 b may be implemented using WaveLAN™ WL60040Multimode Wireless LAN media Access Controller (MAC) from Agere Systemsof Allentown, Pa. U.S.A., whose a product brief is incorporated hereinby reference, which is part of a full chip-set as described in WaveLAN™802.11a/b/g Chip Set document from Agere Systems of Allentown, Pa.U.S.A., which is incorporated herein by reference. Reference is made tothe manufacturer's data sheet Agere Systems, WaveLAN™ WL60040 MultimodeWireless LAN Media Access Controller (MAC), Product Brief August 2003PB03-164WLAN, which is incorporated herein by reference.

Some wireless technologies, in particular microwave signals used in theWAN and MAN arenas, are using frequencies above 2-3 GHz where the radiopath is not reflected or refracted to any great extent. Propagation insuch frequencies requires a Line-of-Sight (LOS) relying on a line ofsight between the transmitting antenna and the receiving antenna. Usingthis concept allows for NLOS (Non-LOS) wireless networks to interconnectover a LOS-based communication link. In addition, the wirelesstechnology implemented may use either licensed frequency bands orunlicensed frequency bands, such as the frequency bands utilized in theIndustrial, scientific and Medical (ISM) frequency spectrum. In the US,three of the bands within the ISM spectrum are the A band, 902-928 MHz;the B band, 2.4-2.484 GHz (referred to as 2.4 GHz); and the C band,5.725-5.875 GHz (referred to as 5 GHz). Overlapping and/or similar bandsare used in different regions such as Europe and Japan. Further,cellular technologies can also be used, commonly using licensedspectrum. Such digital technologies include GSM (Global System forMobile Communications), GPRS (General Packet Radio Service), CDMA (CodeDivision Multiple Access), EDGE (Enhanced Data Rates for GSM Evolution),3GSM, DECT (Digital Enhanced Cordless Telecommunications), Digital AMPS(per IS-136/TDMA, for example) and iDEN (Integrated Digital EnhancedNetwork). The service carried over the cellular network may be voice,video or digital data such as the recently introduced EVDO (EvolutionData Only). In one embodiment, a WirelessHD standard based wirelesscommunication is employed, which is based on the 7 GHz of continuousbandwidth around the 60 GHz radio frequency and allows for uncompressed,digital transmission.

Digital cameras utilizing wireless communication are disclosed in U.S.Pat. No. 6,535,243 to Tullis entitled: “Wireless Hand-Held DigitalCamera”, U.S. Pat. No. 6,552,743 to Rissman entitled: “DigitalCamera-Ready Printer”, U.S. Pat. No. 6,788,332 to Cook entitled:“Wireless Imaging Device and System”, and in U.S. Pat. No. 5,666,159 toParulski et al. entitled: “Electronic camera system with programmabletransmission capability”, which are all incorporated in their entiretyfor all purposes as if fully set forth herein. A display system andmethod utilizing a cellular telephone having digital camera capabilityand a television linked directly over a UWB wireless signal is disclosedin U.S. Pat. No. 7,327,385 to Yamaguchi entitled: “Home Picture/VideoDisplay System with Ultra Wide-Band Technology”, which is incorporatedin its entirety for all purposes as if fully set forth herein.

As described above, communication based on electromagnetic waves invarious parts of the electromagnetic spectrum can be used forcommunication. For example, low-frequency electromagnetic radiation canbe used to transmit audio-frequency signals over short distances withouta carrier. Radio-frequency transmission is a special case of thisgeneral electromagnetic transmission. As noted previously, light is alsoa special case of electromagnetic radiation, but is herein treatedseparately because of the characteristics of light are distinctlydifferent from those of electromagnetic transmission in other usableparts of the electromagnetic spectrum.

Non-wired communication accomplished by light, either visible ornon-visible light wavelength, can be used for the above transmission.The most popular is infrared (IR) based communication, but ultravioletmay also be used. Most such systems require substantially‘line-of-sight’ access. In such a system, the antenna 552 b relating tothe camera 16 is replaced with light emitter (e.g. LEDs), and theantenna 552 a relating the control box 553 will be replaced with lightdetectors (e.g. photoelectric cell), and the communication over the airrelies on the propagation of light.

Similarly, sound-based communication over space may be used, wherein thetransceivers 551 a and 551 b use microphones and speakers, and thecommunication relies on the propagation of sound waves through the airin the space. Either audible sound (20-20,000 Hz band), or inaudiblesound (ultrasonic, above 20,000 Hz; or infrasonic, below 20 Hz) can beused. In this case, the antennas 552 a and 552 b are substituted with amicrophone or a similar device converting the sound signal into anelectrical signal, and a speaker or a similar device for generating theaudio signal and transmitting it to the air. A transducer combining intoa single device both the speaker and the microphone functionalities mayalso be used. Since these solutions do not require any physicalconnection, such as cable, they provide both ease-of-use and mobility.Such non-wired solutions are effective over short distances.Furthermore, most of the non-wired solutions cannot easily pass throughwalls and other such obstructions, owing to the attenuation to thesignals. Hence, such techniques are suitable for communication within asingle room, but are not suitable for communication between the rooms ofa home or other building.

While the invention has been exampled above with regard to a camera 16mechanically attached to display 18, it will be appreciated that theinvention equally applies to the case wherein there is no suchmechanical attachment. For example, the camera 16 may be in a differentroom from the display 18, but still uses the face detection or handgesture detection to control the display 18 located in the other room.

While the invention has been exampled above with regard to controlling adisplay 18 (either the display 18 positioning, power supplying to thedisplay 18 or any other control), it will be appreciated that theinvention equally applies to any other visualization device to becontrolled. Examples are television set, video projector,rear-projection TV. Further, audio devices may as well be controlled,such as speakers. Further, any type of a device may be equally usedaccording to the invention.

While the invention has been exampled above with regard to capturing,transmitting and processing a visible image, it is apparent that anon-visible spectrum can be equally used, such as infrared andultraviolet. In such a configuration, the infrared image is captured,and then processed by the image processor 12. In such a system, thesensor 72 in FIG. 7 is sensitive to the non-visible part of the lightspectrum (e.g. infrared).

In another embodiment of a non-conductive network medium, a fiber opticcable is used. In such a case, transceivers 551 a and 551 b are fiberoptic transceivers, and similarly antennas 552 a and 552 b are replacedwith a fiber optic connector. As such, the term ‘wiring’ and ‘cable’ inthis application should be interpreted to include networks based onnon-conductive medium such as fiber-optics cabling.

Powerline communication is known in the art for using the AC power wiresin a building for digital data communication. Traditional approaches topowerline communication (e.g., home or office) include applications suchas control of lighting and appliances, as well as sending data orbroadband data, video or audio. Powerline command communication systemsinclude for example X-10, CEBus (Consumer Electronics Bus per EIA-600standard), and LonWorks.

The HomePlug organization is an industry trade group for powerlinecommunication including various entities to define powerlinecommunication specifications. HomePlug 1.0 is a specification for a homenetworking technology that connects devices to each other through powerlines in a home. HomePlug certified products connect PCs and otherdevices that use Ethernet, USB, and 802.11. Many devices made byalliance members have HomePlug built in and connect to a network uponplugging the device into a wall socket in a home with other HomePlugdevices. Signal interference, from surge protectors, extension cords,outlet strips and/or other proximately located devices, including thehigh-frequency signals, is an on-going concern of the HomePlug alliance.Similarly, HomePlug AV (HPAV) is a new generation of technology from theHomePlug Powerline Alliance. HPAV can be for example embedded inconsumer electronics or computing products, and provides high-quality,multi-stream, entertainment-oriented networking over existing AC wiring.Users can avoid having to install new wires in their premises by usingdevices having built-in HomePlug technology. HPAV uses advanced PHY andMAC technologies that provide a 200 Mbps (million bits per second) classpowerline network for inter alia video, audio and data. The Physical(PHY) Layer utilizes this 200 Mbps channel rate to provide a 150 Mbpsinformation rate to provide communications over noisy power linechannels. As used herein, the terms “powerline” and “powerlinecommunications” refer to any technology that is used to transfer data orsignals over a power distribution system, including without limitationUPB, HomePlug, HomePlug a/v, and X-10 technologies. As used herein, theterm “UPB” or Universal Powerline Bus refers to one exemplary instanceof technologies which impose digital or analog signals or pulses onto ACwaveforms or DC power delivery systems, such as for example the wellknown UPB approach set forth in “Universal Powerline Bus: The UPB SystemDescription”, Version 1.1 dated Sep. 19, 2003, incorporated herein byreference in its entirety. Lastly, the term “HomePlug” as used herein ismeant specifically to include devices and systems compliant with theHomePlug™. Powerline Alliance Specification for powerline-based homenetworks (including the more recent HomePlug A/V), and generally toinclude all other comparable devices adapted for powerline networking.

In one embodiment according to the invention, powerline communication isused for the interconnection between the camera 16 and the control box11, such as HomePlug based communication. One advantage in such aconfiguration is that only a single power cable is used, carrying boththe AC power and the communication signal. Such a camera 591 is shown inFIG. 59 adapted from camera block diagram shown in FIG. 7. A low passfilter 572 b is disposed between the AC power plug 21 and the powersupply 78, for passing only the AC power signal, such as the 50 Hz orthe 60 Hz. Such a low pass filter 572 b also stops and exhibits highimpedance in the digital data frequency band, thus reducing impedanceloading at this frequency band. Transceiver 75 of FIG. 7 is replacedwith a powerline modem 574 b, connected to the AC power wires via a highpass filter 573 b, which passes only the digital data frequency band,hence allowing only the digital data signal to pass, while stopping theAC power. If HomePlug technology is used, the modem is a HomePlugcompliant modem, and the communication (physical layer and higherprotocol layers) is implemented according to the HomePlug specificationstandard. As an example, such modem can be based on INT6000 ‘HomePlug AVHigh-Speed Powerline Solution’ available from Intellon Corporation,headquartered in Orlando, Fla., U.S.A.

Similarly, control box 571, shown in FIG. 57 as part of system 570, isalso adapted to support powerline communication, in order to communicatewith a mating camera 591 of FIG. 59. Low pass filter 572 a is addedbetween the AC power plug 21 and the power supply 19. A powerline modem574 a is added, connected to the AC power wires 22 via high pass filter573 a, which passes only the digital data frequency band, hence allowingonly the digital data signal to pass, while stopping the AC power. IfHomePlug technology is used, the modem is a HomePlug compliant modem,and the communication (physical layer and higher protocol layers) isimplemented according to the HomePlug specification standard.

Similarly, the communication of a control information between thecontrol box and the display is also adapted to support powerlinecommunication, as shown as system 600 in FIG. 60, adapted from system420 in FIG. 42. The control box 601, shown in FIG. 60 as part of system600, is also adapted to support powerline communication, in order tocommunicate with a mating display 18. Low pass filter 572 a is addedbetween the AC power plug 21 a and the power supply 19. A powerlinemodem 574 a is added, connected to the AC power wires 22 a via high passfilter 573 a, which passes only the digital data frequency band, henceallowing only the digital data signal to pass, while stopping the ACpower. Similarly in the display 18 side, low pass filter 572 b is addedbetween the AC power plug 21 b and the power supply connection of thedisplay 18. A powerline modem 574 b is added, connected to the AC powerwires 22 b via high pass filter 573 b, which passes only the digitaldata frequency band, hence allowing only the digital data signal topass, while stopping the AC power. If HomePlug technology is used, themodems 574 a and 574 b are HomePlug compliant modems, and thecommunication (physical layer and higher protocol layers) is implementedaccording to the HomePlug specification standard.

In one embodiment, a wired medium 26 is connected between the camera 16and the image processor 12. The wired medium is a wired communicationmedium, connected to via a connector. Such wired medium may be a UTP,STP, coaxial cable, a telephone wire pair, a CATV coaxial cable, ACpower wire pair and LAN cable, such as Category 5 or Category 6. Asuitable connector may be used for connecting to the specific type ofthe wired medium, such as a coaxial connector for connecting to acoaxial cable and a telephone connector for connecting to a telephonewire pair. The wired medium may be a single non-used twisted-pair in aLAN cable, or two such pairs connected in parallel. In another aspect ofthe present invention, the wired medium is using a phantom channelformed between two wire pairs, such as two twisted wire pairs in a LANcable used in Ethernet 10BaseT, 100BaseTX or 1000BaseT. Similarly, anyPAN, LAN, MAN or WAN wiring may be used as the wired medium.

In the case of wired medium connecting between the camera and the imageprocessor (or between the control box and the controlled unit), a wiredtransceiver is adapter to be a wired modem or a wired transceiver isused, suitable for transmitting and receiving over the appropriatewiring used. The communication over such cable can be proprietary orpreferably using an industry standard communication, wherein theconnections of the camera and of the control box to the cable (as wellas the connection from the control box to the display) are based onstandard connectors and interfaces. The communication may be based on aparallel scheme, wherein multiple wires are used to concurrently carrythe digital data, thus allowing a higher transfer rate of theinformation. In an alternative embodiment, serial communication is used,allowing for few conductors to be used and smaller footprint connectorsrequiring the usage of less pins and contacts. Various standard PAN(Personal Area Network), WAN (Wide Area Network) and LAN (Local AreaNetwork) protocols can be used. In one embodiment, standard LAN (LocalArea Network) is used, such as Ethernet IEEE802.3 10BaseT, 100Base TX or1000BaseT. In such a case the transceiver 34 is Ethernet PHY (i.e.Ethernet physical layer or Ethernet transceiver) that can be implementedbased on “LAN83C180 10/100 Fast Ethernet PHY Transceiver” or “LAN91C11110/100 Non-PCI Ethernet Single Chip MAC+PHY” available fromSMSC—Standard Microsystems Corporation of Hauppauge, N.Y. U.S.A. Whilethis function can be implemented by using a single dedicated component,in many embodiments this function is integrated into a single componentincluding other functions, such as handling higher layers. Thetransceiver may also contains isolation magnetic components (e.g.transformer-based), balancing components, surge protection hardware, anda LAN connector (commonly RJ-45) required for providing a proper andstandard interface via a connector. In one embodiment, standard cablingis used, such as standard LAN cabling. For example, Category 5 cabling(‘structured wiring’) or any other wiring according to EIT/TIA-568 andEIA/TIA-570 can be used. Such LAN cabling involves wire pairs that maybe UTP or STP. Similarly, category 3, 4, 5 e, 6, 6 e and 7 cables may beequally used. Such configuration is described, for example, inEIT/TIA-568 and EIA/TIA-570. It will be appreciated that any wiredinterface, other than Ethernet 10/100BaseT described above, beingproprietary or standard, packet or synchronous, serial or parallel, maybe equally used, such as IEEE1394, USB (Universal Serial Bus),EIA/TIA-232, PCI (Peripheral Component Interconnect), PCMCIA (PersonalComputer Memory Card international Association), or IEEE1284, but notlimited to the aforementioned. Furthermore, multiple such interfaces(being of the same type or mixed) may also be used.

In the cases wherein a conductive medium, such as a dedicated cable, isused as the communication medium between the camera and the control box,it may be preferred to use the same cable to concurrently carry powerbetween the camera and the control, thus obviating the need for twocables, one for providing power and one for communication purposes. Inone embodiment, the control box is adapted to drive power to the cablefor powering the camera. In alternate embodiment, the camera is adaptedto drive power to the cable for powering the control box. Such power canbe used only for powering the camera module and related functionalities,or for fully powering the control box.

In an alternative embodiment, the power and communication signals arecarried over the wires in the cable using Frequency DivisionMultiplexing (FDM, a.k.a. Frequency Domain Multiplexing). In suchimplementation, the power and the communications signals are carriedeach in its frequency band (or a single frequency) distinct from eachother. For example, the power signal can be a DC (Direct Current) power(effectively 0 Hz), while the communication signal is carried over the100 Hz-10 MHz (or 4-30 MHz) frequency band, which is distinct and abovethe DC power frequency. In one example, a relatively high voltage suchas a 120VDC can be used in order to compensate for the wiring resistancecaused voltage drops. In some installations, safety standards such asUL/IEC 60950 and EN60950 may limit the voltage level in manyapplications to 60VDC. A telephony common 48VDC voltage level may alsobe used.

Another technique for carrying power and data signals over the sameconductors is known as Power over Ethernet (PoE) (i.e., Power overLAN—PoL) and standardized under IEEE802.3af and IEEE802.3 at, alsoexplained in U.S. Pat. No. 6,473,609 to Lehr et al. titled: “StructureCabling System”, which describes a method to carry power over LANwiring, using the spare pairs and the phantom mechanism. The lattermakes use of center-tap transformers. The powering scheme describedabove may use this standard as well as using non-standard proprietarypowering schemes. In one example, USB (Universal Serial Bus) connectionis used for both power and digital data.

The above various states may be each represented by a single dedicatedsingle-state indicator. However, in order to reduce complexity, knowntechniques are commonly used in order to combine signals. Suchtechniques may use different colors (of the same indicator), differentintensity levels, variable duty-cycle and so forth. While visualindicators have been described, other indicating methods may be usedsuch as audible tones (as stand alone or combined with visual).

All publications, patents, and patent applications cited in thisspecifications are herein incorporated by reference as if eachindividual publication, patent, or patent application were specificallyand individually indicated to be incorporated by reference and set forthin its entirety herein.

Those of skill in the art will understand that the various illustrativelogical blocks, modules and circuits described in connection with theembodiments disclosed herein may be implemented in any number of waysincluding electronic hardware, computer software, or combinations ofboth. The various illustrative components, blocks, modules and circuitshave been described generally in terms of their functionality. Whetherthe functionality is implemented as hardware or software depends uponthe particular application and design constraints imposed on the overallsystem. Skilled artisans recognize the interchangeability of hardwareand software under these circumstances, and how best to implement thedescribed functionality for each particular application.

Although exemplary embodiments of the present invention have beendescribed, this should not be construed to limit the scope of theappended claims. Those skilled in the art will understand thatmodifications may be made to the described embodiments. Moreover, tothose skilled in the various arts, the invention itself herein willsuggest solutions to other tasks and adaptations for other applications.It is therefore desired that the present embodiments be considered inall respects as illustrative and not restrictive, reference being madeto the appended claims rather than the foregoing description to indicatethe scope of the invention.

It will be appreciated that the aforementioned features and advantagesare presented solely by way of example. Accordingly, the foregoingshould not be construed or interpreted to constitute, in any way, anexhaustive enumeration of features and advantages of embodiments of thepresent invention.

The present invention may be embodied in other specific forms withoutdeparting from its spirit or essential characteristics. The describedembodiments are to be considered in all respects as illustrative and notrestrictive. The scope of the invention is, therefore, indicated by theappended claims rather than by the foregoing description. All changesthat come within the meaning and range of equivalency of the claims areto be embraced within their scope.

1. An apparatus for signaling based on detecting an element in an image,said apparatus comprising: a digital camera for capturing the image indigital data form; an image processor coupled to receive the image indigital data form from said digital camera, for applying an elementdetection algorithm to detect the element in the captured image; andsoftware and a processor to execute said software coupled to controlsaid image processor and said digital camera; and a port for outputtinga first signal coupled to said processor; wherein said processorproduces the first signal in response to detecting the element in theimage for at least a first time period, followed by detecting theabsence of the element in the image for at least a second time period.2. The apparatus according to claim 1, wherein said digital cameracomprises: an optical lens for focusing received light, said lens beingmechanically oriented to guide the image; a photosensitive image sensorarray disposed approximately at an image focal point plane of theoptical lens for capturing the image and producing an analog signalrepresenting the image; and an analog-to-digital (A/D) converter coupledto said image sensor array for converting the analog signal to a digitaldata representation of the image.
 3. The apparatus according to claim 2,wherein said image sensor array is based on Charge-Coupled Devices (CCD)or Complementary Metal-Oxide-Semiconductor (CMOS).
 4. The apparatusaccording to claim 1, wherein the element is part of a human body. 5.The apparatus according to claim 4, wherein the element is a human face,and wherein said image processor applies a face detection algorithm todetect the image of the human face in the captured image.
 6. Theapparatus according to claim 4, wherein the element is a human hand, andwherein said image processor applies a human hand detection algorithm todetect the image of the human hand in the captured image.
 7. Theapparatus according to claim 6, wherein the element is a hand gesture,and wherein said image processor applies a hand gesture detectionalgorithm to detect the image of the hand gesture in the captured image.8. The apparatus according to claim 7, wherein the hand gesture includesextending a single finger.
 9. The apparatus according to claim 7,wherein the hand gesture includes extending multiple fingers.
 10. Theapparatus according to claim 7, wherein the hand gesture includesextending all fingers of one hand.
 11. The apparatus according to claim1, wherein said image processor is further operative to detect theposition of the element in the captured image.
 12. The apparatusaccording to claim 11, wherein said first signal is produced in responseto the element position in the captured image.
 13. The apparatusaccording to claim 1, said apparatus being further operative to detecttwo elements in the captured image.
 14. The apparatus according to claim13, wherein said first signal is produced in response to detecting thetwo elements in the captured image.
 15. The apparatus according to claim13, wherein the two elements are of the same type.
 16. The apparatusaccording to claim 13, wherein the two elements are of the same shape.17. The apparatus according to claim 13, wherein the two elements aredistinct from each other.
 18. The apparatus according to claim 13,wherein one of the elements is detected based on detection of the otherelement.
 19. The apparatus according to claim 18, wherein one of theelements is detected based on the position of the other element.
 20. Theapparatus according to claim 13, wherein one of the elements is a humanbody part.
 21. The apparatus according to claim 20, wherein the twoelements are human body parts.
 22. The apparatus according to claim 21,wherein one of the elements is a human face.
 23. The apparatus accordingto claim 21, wherein one of the elements is a human hand.
 24. Theapparatus according to claim 23, wherein one of the elements is a handgesture.
 25. The apparatus according to claim 21, wherein one of theelements is a human hand and the other element is a human face.
 26. Theapparatus according to claim 1, wherein said digital camera, said imageprocessor, said port, and said processor are housed within a singleenclosure.
 27. The apparatus according to claim 1, further comprising, asingle enclosure, and a display in said single enclosure, said displayhaving a screen for visually presenting information, said display beingcoupled to be controlled by said processor.
 28. The apparatus accordingto claim 27, wherein said digital camera, said image processor, saidport, and said processor are housed within said single enclosure. 29.The apparatus according to claim 27, wherein said display is coupled tosaid port so that said screen is blanked in response to detecting theelement in the image for at least the first time period, followed bydetecting the absence of the element in the image for at least thesecond time period.
 30. The apparatus according to claim 27, whereinsaid display is part of a television set.
 31. The apparatus according toclaim 30, wherein, said single enclosure is a television set enclosureand said digital camera, said image processor, said port and saidprocessor are housed within the television set enclosure.
 32. Theapparatus according to claim 27, wherein said display is part of apersonal computer.
 33. The apparatus according to claim 32, wherein saidsingle enclosure is an enclosure for the personal computer, and saiddigital camera, said image processor, said port, said display, and saidprocessor are housed within the personal computer enclosure.
 34. Theapparatus according to claim 27, wherein information is displayed onsaid screen in response to the first signal.
 35. The apparatus accordingto claim 27, wherein said digital camera is mechanically attached tosaid display.
 36. The apparatus according to claim 35, wherein saiddigital camera is mounted to capture an image in front of the displayscreen.
 37. The apparatus according to claim 1, wherein: said port is acommunication port for coupling to a network medium; and said apparatusfurther comprises a transceiver coupled to said communication port forcommunicating the first signal over the network medium.
 38. Theapparatus according to claim 37, wherein said communication port is anantenna for over-the-air radio-frequency communication, and wherein saidtransceiver is a wireless transceiver.
 39. The apparatus according toclaim 38, wherein the over-the-air radio-frequency communication uses alicense-free frequency band.
 40. The apparatus according to claim 39,wherein the license-free frequency band is an ISM band.
 41. Theapparatus according to claim 40, wherein the ISM band is 5 GHz or 2.4GHz.
 42. The apparatus according to claim 39, wherein the over-the-airradio-frequency communication takes place in a Wireless Personal AreaNetwork (WPAN), wherein said antenna is a WPAN antenna, and wherein saidwireless transceiver is a WPAN transceiver.
 43. The apparatus accordingto claim 42, wherein the WPAN is according to, or based on, Bluetooth,IEEE 802.15, Ultra-Wide-Band (UWB), or ZigBee.
 44. The apparatusaccording to claim 39, wherein the over-the-air radio-frequencycommunication takes place over a Wireless Local Area Network (WLAN),wherein said antenna is a WLAN antenna, and wherein said wirelesstransceiver is a WLAN transceiver.
 45. The apparatus according to claim44, wherein the WLAN is according to, or based on, IEEE 802.11a,IEEE802.11b, or IEEE802.11g.
 46. The apparatus according to claim 39,wherein the over-the-air radio-frequency communication is a WirelessWide Area Network (WWAN) communication, wherein said antenna is a WWANantenna, and wherein said wireless transceiver is a WWAN transceiver.47. The apparatus according to claim 39, wherein the over-the-airradio-frequency communication is a cellular communication, wherein saidantenna is a cellular antenna, and wherein said wireless transceiver isa cellular transceiver.
 48. The apparatus according to claim 47, whereinthe cellular communication is according to, or based on, GSM (GlobalSystem for Mobile Communications), GPRS (General Packet Radio Service),CDMA (Code Division Multiple Access), EDGE (Enhanced Data Rates for GSMEvolution), 3GSM, DECT (Digital Enhanced Cordless Telecommunications),Digital AMPS, or iDEN (Integrated Digital Enhanced Network).
 49. Theapparatus according to claim 39, wherein the over-the-airradio-frequency communication uses a 60 GHz license-free frequency band,and wherein said over-the-air radio-frequency communication is used forin-room communication.
 50. The apparatus according to claim 49, whereinsaid over-the-air radio-frequency communication is based on beam formingand supports a data rate above 7 Gb/s.
 51. The apparatus according toclaim 50, wherein said over-the-air radio-frequency communication isaccording to, or based on, WirelessHD™.
 52. The apparatus according toclaim 37, wherein communication over the network medium is based onvisible or non-visible light communication.
 53. The apparatus accordingto claim 37, wherein the network medium is a cable, said communicationport is a connector for connecting to the cable, and said transceiver isa wired transceiver.
 54. The apparatus according to claim 53, whereinthe cable is operative for use in a Local Area Network (LAN), whereinsaid connector is a LAN connector, and wherein said wired transceiver isa LAN transceiver.
 55. The apparatus according to claim 54, wherein theLAN is Ethernet based, and is according to, or based on, IEEE 802.3-2008standard.
 56. The apparatus according to claim 55, wherein the cable isbased on twisted-pair copper cables, and wherein said LAN transceiver isaccording to, or based on, 10Base-T, 100Base-TX, or 1000Base-T, andwherein said LAN connector is RJ-45 type.
 57. The apparatus according toclaim 53, wherein the cable is connectable to simultaneously carry a DCor AC power signal.
 58. The apparatus according to claim 57, furtheroperative to output at least part of the power signal to a deviceexternal to the apparatus.
 59. The apparatus according to claim 57,wherein said apparatus is further operative to at least in part bepowered from the power signal.
 60. The apparatus according to claim 57,wherein the power signal is carried over dedicated wires in the cable,and wherein the wires are distinct from wires in the cable carrying thefirst signal.
 61. The apparatus according to claim 57, wherein the powersignal and the first signal are carried over the same wires in thecable, and wherein said apparatus further comprises a power/datasplitter arrangement having first, second and third ports, wherein onlythe first signal is passed between said first and second ports, and onlythe power signal is passed between said first and third ports, andwherein said first port is coupled to said connector.
 62. The apparatusaccording to claim 61, wherein the power and digital data signals arecarried using Frequency Division/Domain Multiplexing (FDM), and whereinthe first signal is carried in a frequency band higher than, anddistinct from, the power signal frequency or frequency band.
 63. Theapparatus according to claim 62, wherein said power/data splitterarrangement comprises a high pass filter between said first and secondports and a low pass filter between said first and third ports.
 64. Theapparatus according to claim 63, wherein said power/data splitterarrangement comprises a transformer having windings and a capacitorconnected to the transformer windings.
 65. The apparatus according toclaim 62, wherein said power and first signals are carried using aphantom scheme.
 66. The apparatus according to claim 65, wherein saidpower/data splitter comprises at least two transformers each having acenter-tap connection.
 67. The apparatus according to claim 57, whereinsaid power and first signals are carried substantially according to IEEE802.3af-2003 or IEEE 802.3 at-2009 standards.
 68. The apparatusaccording to claim 1, wherein power is supplied to or disconnected froma device connected to and external to said apparatus in response todetecting the element in the image for at least the first time period,followed by detecting the absence of the element in the image for atleast the second time period.
 69. The apparatus according to claim 68,further comprising a switch coupled to said processor connected to beactuated in response to the first signal.
 70. The apparatus according toclaim 68, wherein the device is an electromechanical device for movingan article in response to the first signal.
 71. The apparatus accordingto claim 70, wherein the device is an electric motor.
 72. The apparatusaccording to claim 71, wherein the electric motor is a stepper motor.73. The apparatus according to claim 68, wherein the device ismechanically coupled to said digital camera.
 74. An apparatus forsignaling based on detecting an element in an image, said apparatuscomprising: a digital camera for capturing the image in digital dataform; an image processor coupled to receive the image in digital dataform from said digital camera, for applying an element detectionalgorithm to detect the element in the captured image; software and aprocessor to execute said software coupled to control said imageprocessor and said digital camera; and a port for outputting a firstsignal coupled to said processor; wherein said processor produces thefirst signal in response to the absence of the element in the image forat least a first time period.